FINAL AP BIO MCQ

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(melanin synthesis pt 3) Which of the following pieces of evidence would best support the researchers' claim above?

(A) When researchers applied a drug that activates adenylyl cyclase to the mutant mice's ears, the level of melanin increased.

Nucleotide base pairing in DNA is universal across organisms. Each pair (T−A; C−G) consists of a purine and a pyrimidine. Which of the following best explains how the base pairs form?

(melanin synthesis pt 2) Which of the following claims best explains why keratinocytes do not produce melanin?

cortisol

mediates long-term metabolic responses to stress and is produced by the adrenal gland

Transformation-

method of horizontal gene transfer, bacteria takes in plasmids from environment

How are specific antibodies produced?

by WBC, B cell develop from stem cells in bone marrow... when activ they develop into plasma cells and produce antibodies spec to antigen

How are nucleotide monomers connected to form a polynucleotide?

by covalent bonds between the sugar of one molecule and the phosphate of the next.

During aerobic respiration, electrons travel downhill in which sequence?

food ® NADH ® electron transport chain ® oxygen

allopatric speciation

formation of new species in population that are geographically isolated from one another

sympatric speciation

formation of new species in populations that live in same geographic area (ex. from temporal isolation)

Which of the following is not one of the many functions performed by proteins?

forming primary structural component of membranes.

what is founder effect & example

genetic drift that occurs when few individuals become isolated from larger population and form new population whose gene pool composition is not reflective of that of the original population // ex. Galapagos finches

Set point-

"place" comfortable for normal activity, always come back and regulate to this point

# of hydrogen bonds between A and T

# of hydrogen bonds between G and C

Endocrine System-

hormones secreted to extracellular fluid to circulate and communicate messages hormone binds to a SPECIFIC receptor response cells without receptor are unaffected maintain homeostasis sexual matur, growth and devel, mediates response by EXTERNAL STIMULI function: chemcial signal by hormones

Which of the following is mismatched with its description?

phosphate-forms bonds that stabilize protein structure.

The plasma membrane is composed of several different macromolecules. Which macromolecule serves as the fluid interface between the intracellular and extracellular environments?

phospholipids

Which of the following types of molecules are the major structural components of the cell membrane?

phospholipids and proteins

Most life on Earth depends, directly or indirectly, on a process that combines water and carbon dioxide to make carbon-based compounds. This process is called

photosynthesis

first terrestrial organisms

photosynthetic prokaryotes

types of evidence used to make phylogenetic trees

physical similarities // shared DNA & genes

genome euks vs pros

pros- circular chrom, less pro nucleoid euks- linear chromosome nucleus

What molecule carries out most of the activities of life, including the synthesis of all other biological molecules?

protein

collagen

protein

Evaporation-

removal of heat from surfac...liquid lost as gas molecules, cooling

relationship with BMR and Body Mass-

smaller the animal, higher the metabolic rate...due to SA:volume ratio. each gram of mouse requires 20X calories as gram of elephant

The chemical group that confers acidic properties to organic molecules is

-COOH

If cells in the process of dividing are subjected to colchicine, a drug that interferes with the functioning of the spindle apparatus, at which stage will mitosis be arrested?

D) metaphase

What is the term for the process of analyzing sections of DNA that may have little or no function but that vary widely from one individual to another? A. DNA polymerase B. DNA fingerprinting C. Gene therapy D. Forensics

DNA fingerprinting

Nucleotides

DNA is a polymer consisting of repeating units of ___

Response in Endo vs Nerv

Endo- 1 location or many Nerv- nerve impulses

Signal ENdo vs Nervous

Endo- molecules (hormones) Nervous- nerve impulses

Which of the following is a statement of the first law of thermodynamics?

Energy cannot be created or destroyed.

Which of the following statements best explains the role of Enzyme 1 in the DNA replication process?

Enzyme 1 is a topoisomerase that relieves tension in the overwound DNA in front of a replication fork.

Restriction enzymes

Enzyme capable of cutting DNA at specific sequences, work by binding to specific base sequence and cleaving DNA backbone in 2 locations on 1 strand

Catabolism is an anabolism as _________________ is to _______________.

Exergonic; endergonic

12/6 C, 16/8 O, 1/1 H, 14/7 N, 32/16 S, 31/15 P How many covalent bonds is a sulfur atom most likely to form?

Starting with a fertilized egg (zygote), a series of five cell divisions would produce an early embryo with how many cells?

A F1 plant that is homozygous for tallness is crossed with a heterozygous F1 plant. What ratio of tall to short plants (tall:short) represents the possible offspring? A. 4:0 B. 1:1 C. 1:3 D. 3:1

4:0

The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are in the alpha form. Which of the following could amylase break down?

Glycogen, starch, and amylopectin

Which of the following produces and modifies polysaccharides that will be secreted?

Golgi apparatus

Over the next year, a virus attacks and rapidly kills almost all plants of the tobacco species. A closely related species of tobacco that is resistant to the virus becomes established during that same year. The nectary tube in the resistant species averages 7.5cm. Scientists monitored the area for the next five years to determine how this change affected the moth population. Which of the following best describes the expected distribution of proboscis size of the moths at the end of the five‑year study?

Graph A.

Which of the following best explains a distinction between metaphase I and metaphase II?

Homologous pairs of chromosomes are aligned during metaphase II, but individual chromosomes are aligned during metaphase IIII.

Which molecule is a saturated fatty acid?

49) Spherocytosis is a human blood disorder associated with a defective cytoskeletal protein in the red blood cells (RBCs). What do you suspect is the consequence of such a defect? A) abnormally shaped RBCs B) an insufficient supply of ATP in the RBCs C) an insufficient supply of oxygentransporting proteins in the RBCs D) adherence of RBCs to blood vessel walls, causing plaque formation

Deletion

Loss of one letter to DNA sequence

The cellular structure that is involved in producing ATP during aerobic respiration

MItochondria

Which of the following statements describes NAD+?

NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle.

5' to 3'

New DNA strand is synthesized from

hydrocarbon

Only Hydrogen and Carbon in the molecule

Which is not true??

Only bacteria have histones associated with DNA

Movement of water across a membrane from a region of higher concentration of water to a region of lower concentration

Osmosis

Which of the following best describes the contents expected to be contained in one of the five control test tubes?

PH 4 buffer solution and hydrogen peroxide only.

Natural selection selects for or against

Phenotypes

Prokaryotic and eukaryotic cells share what features

Plasma Membrane

Movement of water out of a cell resulting in the collapse of the plasma membrane

Plasmolysis

Which statement below best states an alternative hypothesis Fox could have used to frame his research?

In the presence of available energy and the absence of a significant quantity of atmospheric O2 simple proteins will form spontaneously from a mixture of amino acids.

why organisms found in India differ from those in Indonesia

India was a separate continent due to tectonic plates

How can a small change in a person's DNA cause a genetic disorder? A. A change in a nitrogenous base can result in a translocation. B. None of the other answer choices C. It can alter the amino acid sequence of a protein, changing its structure and function. D. The deletion of a single nucleotide can result in a translocation.

It can alter the amino acid sequence of a protein, changing its structure and function.

Which of the following statements best helps explain how the lead ion causes inhibition of ALAD?

It changes the 3-D structure of the active site so that ALAD is no longer compatible with substrate.

Which of the following best describes an advantage of the phenotypic plasticity displayed by the tadpoles?

It gives the tadpoles increased versatility with respect to diet.

In liver cells, the inner mitochondrial membranes are about five times the area of the outer mitochondrial membranes. What purpose must this serve?

It increases the surface for oxidative phosphorylation.

What happens when a protein denatures?

Its secondary and tertiary structures are disrupted.

Which of the following claims best explains why keratinocytes do not produce melanin?

Keratinocytes do not express the MITF gene.

which species is most likely to become extinct

Kirtlands warbler, which breeds only in a small area of Michigan

Which of the following best explains a process occurring between point 1 and point 2 in Figure 3 ?

A poly‑A tail is added to RNA

Translation

Process by which the codons of an mRNA sequence are changed into an amino acid sequence

Histone acetylation

Promotes loosening of that chromatin structure and permits transcription

A and G

Purines nitrogen bases

The cystic fibrosis gene is A. dominant. B. recessive. C. codominant. D. segregated.

Recessive

Genetically engineered DNA molecules, pieces of which are extracted from various sources and chemically joined together, are called A. transfer RNA. B. recombinant DNA. C. None of the other answer choices D. messenger DNA.

Recombinant DNA

how do amoeba exchange materials?

SA is in contact with the environment have direct exchange

Recombinant-DNA technology can be used in all of the following except A. treating disease. B. preventing disease. C. studying the environment. D. medical research.

Studying the environment

Based on the data in Table 1, which of the following best describes the relationship between the MC1R gene and coat color in the Carrizozo, New Mexico, rock pocket mouse population?

The MC1RD allele is not responsible for dark coat color in the Carrizozo population, so the dark coat color is likely a result of convergent evolution.

Which of the following claims about the TYR, TRP2, and TRP1 mammalian genes is most likely to be accurate?

The TYR, TRP2, and TRP1 genes may be located on different chromosomes but are activated by the same transcription factor.

The critical value is 7.82, and the null hypothesis can be rejected because the calculated chi-square value is greater than the critical value.

The following ribose molecule contains how many asymmetric carbons?

Which of the following best explains how the results should be interpreted?

The individual has an increased risk of developing colon cancer.

DNAase is an enzyme that catalyzes the hydrolysis of the covalent bonds that join nucleotides together. What would first happen to DNA molecules treated with DNAase?

The phosphodiester bonds between deoxyribose sugars would be broken.

A certain type of specialized cell contains an unusually large amount of rough endoplasmic reticulum (ER). Which of the following functions is this cell type most likely specialized to perform?

The production and secretion of proteins

Which of the following outcomes will most likely result from the inactivation of the beta-2 adrenergic receptor?

The rate of glycogen in the cell will increase.

Which of the following statements correctly describes any chemical reaction that has reacher equilibrium?

The rates of the forward and reverse reaction are equal.

Which of the following provides an accurate calculation of the surface area to volume ratio of an HS red blood cell, as well as a prediction of its affect on the efficient transferring of oxygen compared to a normal red blood cell?

The ratio is 0.89, and the cells are LESS efficient at transferring oxygen.

Which of the following statements provides reasoning that supports the claim that brown fatty tissue keeps an animal warm?

The uncoupling protein in this tissue reduces the proton gradient across the membrane and thus produces heat to warm the animal without ATP production.

Which of the following is true regarding saturated fatty acids?

They are the principal molecules in lard and butter.

Why are C4 plants able to photosynthesize with no apparent photorespiration?

They fix CO2 into a 4 carbon compound like malate

Which of the following statements concerning unsaturated fats is true?

They have double bond in the carbon chains of their fatty acids.

Missense mutation

When point/frameshift mutations change a codon within a gene into a stop codon

Which of the following would most likely represent the types of individuals found in one of the species resulting from shape becoming a prezygotic isolating mechanism in the initial population represented in Figure 1 ?

White Circle Gray Circle Black Circle

Answer to previous question:

a phospholipid

The centromere is a region in which

a) chromatids remain attached to one another until anaphase

when 2nd meiotic division occurs in oogenesis

after fertilization occurs in the adult

Changing a single amino acid in a protein consisting of 325 amino acids would

always alter the primary structure of the protein, sometimes alter the tertiary structure of the protein, and sometimes affect its biological activity.

answer to previous card:

an amino grouop

The movement of potassium into an animal cell requires

an energy source such as ATP

A hydration shell is likely to form around

an ion and a sugar

The hydrogen bonds shown in this figure are each between

an oxygen and a hydrogen atom of different water molecules

Diff between shared ancestral and shared derived-

ancestral- ancestor had derived- ancestor didn't have

Claudistics-

another systematic common ancestry is primary criterion

Ex of why difference between analogy and homology is critical-

bats and birds both fly, but theyre not related. a bat's wing is more similar to forelimbd of cat and other mammals bats and birds descended from CA who could not fly skeletal systems are homologous, wings are not. bats- stretched membranes birds- feathers ANALOGOUS

cellulose

carb

What is the term for metabolic pathways that release stored energy by breaking down complex molecules?

catabolic pathways

warming the hypothalamus

causes body temperature to lower by bialating blood vessels to skin or sweating/panting

Which structure is NOT part of the endomembrane system?

chloroplast

Which structure is not part of the endomembrane system?

chloroplast

Which of the following is a typical component of the plasma membrane of a eukaryotic cell

cholesterol

Which of the following molecules is the most hydrophobic?

cholesterol

Countercurrent exchange-

closed circulatory system, cold pipes are next to the warm, move from extremeties...cold blood runs past warm..warms it up

Evidence that birds descended from dinosaurs-

closest living relative of birds are crocodiles both have 4 chamber hearts, sing to defend territories and attract mates, build nests, care for eggs by brooding and parent warms the egg

What accounts for the movement of water up the vessels of a tall tree?

cohesion, hydrogen bonding, adhesion, and hydrophilic cell walls

The difference between the sugar in DNA and the sugar in RNA is that the sugar in DNA

contains one less oxygen atom.

Where does glycolysis take place in eukaryotic cells?

cyplasm (cytosol)

trobic hormones

directs and controls activities of other endocrine glands

whale exchange materials-

each cell has an exchange across membrane only works if every cell has access to suit aqueous env. spec surfaces, extend or branched increase SA

Molecules with which functional groups may form polymers via dehydration reactions?

either hydroxyl or carboxyl groups

In chemiosmosis, what is the most direct source of energy that is used to convert ADP + mc030-1.jpgi to ATP?

energy released from movement of protons through ATP synthase, down their electrochemical gradient

Whenever energy is transformed, there is always an increase in the

entropy of the universe.

plasmids in euks vs pros-

euks mito and chloro pros- addit DNA replication

Each water molecule is capable of forming

four hydrogen bonds

Which of the following is not a polymer?

glucose

INtegumentary system-

hair, skin, nials

A cation

has a positive charge.

counter current heat exchange

heat is exchanged between blood vessels carrying blood in opposite directions

A monosaccharide with six carbons is called ____.

hexose

Function and Location of Connective tissue-

holds tissue and organs together in place (strength and flexibility, join tissue, elasticity) location- blood, cartilage, adipose tissue, skin

Transduction-

horiz, bacteria acquire new DNA from a phage

Reactions that use the equivalent of a water molecule to break a molecule into smaller subunits are called ___ reactions.

hydrolysis

ketone

if the carbonyl group is within a carbon skeleton

Water passes quickly through cell membranes because

it moves through aquaporins in the membrane

Carbon's valence of four most directly results from

its four electrons in the valence shell that can form four covalent bonds.

All of the following are polysaccharides except

lactose.

How do scientists avoid ambiguity when naming species and animals/organisms?

latin scientific names first part- genus to which species belongs second part- specific epithet, which is unique to species within a genus Panthera pardus--italicized Homo sapiens Genus is homo species is homo sapiens

effect of locations and types of mutations on proteins // intron

least harmful mutation

molecular clock

method for estimating time required for a given amount of evolutionary change

basal metabolic rate-

minimum metabolic rate of endotherms

What is not found in a prokaryotic cell?

mitochondria

Where does ATP synthesis occur?

mitochondria and chloroplasts

Where are the proteins of the electron transport chain located?

mitochondrial inner membrane

In what type of bond would you expect potassium (39/19K) to participate?

ionic, it would lose one electron and carry a positive charge.

Based on Table 4-1 and Figure 4-7, what percent of the life cycle of yeast cells is spent in DNA replication? A) 5 percent B) 10 percent C) 25 percent D) 50 percent

C) 25 percent

Based on Figure 1-7, which of the following is a common feature of the illustrated reactions showing the linking of monomers to form macromolecules? A) Two identical monomers are joined by a covalent bond B) Two different monomers are joined by a covalent bond. C) Monomers are joined by a covalent bond, and a water molecule is produced. D) Monomers are joined by ionic bonds, and a water molecule is produced.

C) Monomers are joined by a covalent bond, and a water molecule is produced.

DNA is replicated at this time of the cell cycle:

C) S

What is a genome?

C) The complete complement of an organism's genes

In what way do the membranes of an eukaryotic cell vary?

Certain proteins are unique to each membrane.

Changing the deoxyriboses to riboses by adding −OH groups -RNA contains ribose, whereas DNA contains deoxyribose. A ribose sugar has an −OH group linked to the 2′ carbon that a deoxyribose sugar does not have

37) In a liver cell detoxifying alcohol and some other poisons, the enzymes of the peroxisome remove hydrogen from these molecules and _____. A) combine the hydrogen with water molecules to generate hydrogen peroxide B) use the hydrogen to break down hydrogen peroxide C) transfer the hydrogen to the mitochondria D) transfer the hydrogen to oxygen molecules to generate hydrogen peroxide

After surveying 100 parents, researchers concluded that 90 percent of babies can walk by the age of 10 months. Why is this an inappropriate conclusion? (A) The researchers should have conducted an experiment. (B) The cerebellum is completely developed by ten months. (C) A case study would have yielded more reliable data. (D) At 10 months, ninety percent of toddlers have not reached the developmental milestones to walk. (E) At 10 months, seventy percent of toddlers can walk.

How do the daughter cells at the end of mitosis and cytokinesis compare with their parent cell when it was in G1 of the cell cycle?

D) The daughter cells have the same number of chromosomes and the same amount of DNA.

Parts of the taxonomic system-

DOMAIN KINGDOM PHYLUM CLASS ORDER FAMILY GENUS SPECIES

Central Dogma of biology

From DNA to RNA to RNA directing assembly of proteins

Which prediction of the effect of this disruption of cellular compartmentalization is most likely correct?

Hydrolytic enzymes will be released, which will cause cell death.

mRNA

Involved in transcription

A buffer

Is often a weak acid-base pair.

Which of the following best explains how the leaves from the same plant can have different stomatal densities when exposed to an elevated carbon dioxide level?

Leaf growth is promoted through increased photosynthesis, but the genetically regulated rate of stomatal production is not altered, leading to a decrease in stomatal density.

Which of the following statements is true regarding the molecule illustrated in Figure 5.3?

Molecules of this type are usually liquid at room temperature.

Hydrogen bonds

Nitrogenous bases of opposite chains are paired to one another by

A woman develops Huntington's disease. Her father had the disorder. Her mother did not, and there is no history of the disorder in the mother's family. Which of the following best explains how the woman inherited Huntington's disease?

She inherited an allele with more than 40 CAG repeats in the HTT gene from her father.

Given the results shown in Figure 1, which of the following correctly describes a relationship between the two species?

Species B has more short fragments of DNA than species A does

Evolutionary Adv of Torpor and Hibernation-

TOrpor- decrease activ, save E to avoid dangerous conditions Hibernation- temp decrease, survive through winters on limited food..

Which test tubes are controls in the experiment?

Test tubes 1, 3, 5, and 7

Which of the following statements correctly explains the observed effect of the acetylcholine concentration on the rate of the enzyme catalyzed reaction?

The active site of AChE is specific for acetylcholine, and only one substrate molecule can occupy the active site at a time.

A researcher claims that the phycobiliprotein Pigments in cyanobacteria allow the cyanobacteria to survive in certain aquatic niches better than green algae can. Which of the following statements best justifies the researchers claim?

The additional pigments absorb light at wavelengths that green algae cannot absorb; this may allow cyanobacteria to capture more light energy for photosynthesis than green algae can in certain areas.

Which of the following statements best explains how the fur color can be different in Himalayan rabbits raised under different temperature conditions?

The environment determines how the genotype is expressed.

Which feature of model 1 best illustrates how biological information is coded in a DNA molecule?

The linear sequence of the base pairs

The solutions in the two arms of this U-tube are separated by a membrane that is permeable to water and glucose but not to sucrose. Side A is half-filled with a solution of 2 M sucrose and 1 M glucose. Side B is half-filled with 1 M sucrose and 2 M glucose. Initially, the liquid levels on both sides are equal. After the system reaches equilibrium, what changes are observed?

The water level is higher in side A than in side B

Which of the following statements concerning saturated fats is not true?

They have multiple double bonds in the carbon chains of their fatty acids.

Transformation

Transfer of genetic material from one cell to another, can alter genetic make up of cell. Provides a mechanism for recombinant DNA in bacteria

What can be produced when recombinant DNA is inserted into the genome of a host organism? A. Allele B. Transgenic organism C. Inbred organism D. Plasmid

Transgenic Organism

Repression

Type of operon Trp

Based on the data scientist claim that the reproductive behavior of European flycatchers is influenced by the availability of energy sources. Which of the following statements best justifies this claim?

Young European flycatchers hatch from eggs when caterpillar biomass is available for the young birds to consume and convert into energy for growth.

Which of the following, when mixed with water, would form a colloid?

a large hydrophilic protein

The oxygen consumed during cellular respiration is involved directly in which process or event?

accepting electrons at the end of the electron transport chain

Chromosomes begin migrating to opposite poles

anaphase

Diabetes mellitus

body isn't making enough insulin to control blood sugar levels occurs when some or all of insulin producing cells are destroyed sugar accum autoimmune

The substance H2O is considered to be

both a molecule and a compound

Which of the following describes a critical role of cAMP during the transduction stage of a G protein signal transduction pathway?

cAMP results in the activation of an enzyme that amplified the signal by acting on many substrate molecules.

chitin

carb

glycogen

carb

An organic compound that is composed of carbon, hydrogen, and oxygen is a 1:2:1 ratio is known as a

carbohydrate

Which of the following categories includes all others in the list?

carbohydrate

A molecule with the chemical formula C6H12O6 is probably a

carbohydrate and monosaccharide only.

Recall the structure of a typical amino acid and how the molecule has two distinct "ends". Which two funtional groups are always found in amino acids?

carboxyl and amine

Practical applications of Phylogenetics-

corn- originated in Americas, now worldwide from phylogeny of DNA, researches ID two species of wild grass that are related to corn served as reservoirs, beneficial alleles transferred to cultivated corn by cross breeding or genetic engineering

Based on the figure given below, which of these experimental treatments would increase the rate of sucrose transport into the cell?

decreasing extracellular pH

The process by which protein conformation is lost or broken down is

denaturation

Why CA heterotroph-

every org uses glycolysis, process use din heterotrophic orgs to catabolize food almost all euks have mitochondria, but only som ehave chloro....shows mito came first

why would genes in different species have a high degree of homology

genes code for protein with specific function and the gene can be highly conserved

what allows gene to act as molecular clock

genes must have a reliable average rate of mutation

Breeders can increase the _____ in a population by introducing _____, which are the ultimate source of biological diversity. A. genetic variation; mutations B. genetic variation; inbreeding C. enzymes; mutations D. selective breeding; inbreeding

genetic variation; mutations

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule?

glycolysis

feedforward information

information that changes the set point of the system

chemical groups of hormones

lipid: steroid (non-polar), easily go through membrane

Which structure-function pair is mismatched?

microtubule; muscle contraction

Movement of vesicles within the cell depends on what cellular structures?

microtubules and motor proteins

Which of the following are least soluble in water?

non-polar molecules

polar body

nonfunctional nucleus, produced by meiosis during oogenesis, haploid, contains little cytoplasm, found in ovaries

parthenogenesis

offspring can develop from unfertilized eggs

where MHC class I proteins are found

on the surface of most cells in the mammalian body

A set of five additional test tubes were prepared and used as controls. Which of the following best describes the contents expected to be contained in one of the five control test tubes?

pH 4 buffer solution and hydrogen peroxide only

Which of the following substances is the major component of the cell membrane of a fungus?

phospholipids

Thermoregulation-

process by which organisms maintain tolerable internal temperature

enzyme

protein

hemoglobin

protein

Both hydrophobic and hydrophilic interactions are important for which of the following types of molecules?

proteins

In mitochondria, exergonic redox reactions

provide the energy that establishes the proton gradient.

Which of the following does not occur during the Calvin cycle?

release of oxygen

stabilizing selection

removes extreme variants from population & preserves intermediate types

Retroviruses such as HIV and hepatitis B virus use RNA as their genetic material rather than DNA. In addition, they contain molecules of reverse transcriptase, an enzyme that uses an RNA template to synthesize complementary DNA. Which of the following best predicts what will happen when a normal cell is exposed to a retrovirus?

(C) The reverse transcriptase will produce DNA from the viral RNA, which can be incorporated into the host's genome and then transcribed and translated.

(melanin synthesis pt 6) Which of the following best predicts the phenotype of an individual who is homozygous for this TYR mutation?

(D) The mutation will change all subsequent amino acids in the TYRTYR protein, leading to nonfunctional TYRTYR protein. Individuals with this mutation will lack melanin in their hair, skin, and eyes and will not tan in response to UVUV radiation.

Lipid Soluble Pathway-

(hormone receptors in cytosol prior) 1. steroid hormone binds to cytosolic receptor 2. hormone receptor complex forms and moves into the nucleus 3. receptor portion alters transcription of certain genes ex: estrogen (estradiol) in liver, birds transports to produce yolk

Which level of protein structure do the helix and the pleated sheet represent?

secondary

What aspects of protein structure are stabilized or assisted by hydrogen bonds?

secondary, tertiary, and quaternary structures, but not primary structure

directional selection

shifts overall makeup of population by favoring variants that are at one extreme of the distribution

types of evidence that all living things have a common ancestor

universal genetic code // homologous structures // vestigial structures

Why DNA in CA

universal language, all orgs use

The molecule shown in Figure 5.3 is a(n)

unsaturated fatty acid.

How many degrees of freedom should be used when looking up the critical value for a chi-square analysis of the ratios of phenotypes observed among the F2 offspring versus the expected phenotypic ratio assuming independent assortment?

12/6 C, 16/8 O, 1/1 H, 14/7 N, 32/16 S, 31/15 P A radioactive isotope of carbon has the mass number 14. How many neutrons does this isotope have?

35) Thylakoids, DNA, and ribosomes are all components found in _____. A) chloroplasts B) mitochondria C) lysosomes D) nuclei

9. Which of the following pairs of alleles shows a homozygous dominant pair? a. XX b. Xx c. xx d. All of the above e. None of the above

A member of a population of genetically identical cells produced from a single cell is A. a plasmid. B. an allele. C. a genetic marker. D. a clone.

A clone

Which list of components characterizes RNA

A phosphate group, ribose, and uracil

How does the sexual life cycle increase the genetic variation in a species?

A) By allowing independent assortment of chromosomes

Based on Figure 4-3, which of the following changes in the FGFR signaling pathway is most likely to result in uncontrolled cell proliferation? A) The irreversible association of FGFR proteins B) The loss of the FGFR protein kinase function C) A decrease in the intracellular concentration of ATP D) A decrease in the extracellular concentrations of fibroblast growth factors

A) The irreversible association of FGFR proteins

Figure 1. Relative abundance of plankton over time in the eastern equatorial Pacific Ocean Which of the following observations would best support this alternative hypothesis?

A. Previous dips in plankton abundance coincided with other El Niño events.

Which of the following best explains how bacteria can be genetically engineered to produce a desired antigen?

A. The gene coding for the antigen can be inserted into plasmids that can be used to transform the bacteria.

The researcher claims that there is no selective advantage to fur color, so light and dark fur color phenotypes are present in similar frequencies in the fourth generation of this mouse population. Based on the data in Figure 1, which of the following best evaluates this null hypothesis?

A. The null hypothesis is rejected, because the change to a darker background color led to an increase in the dark-colored fur phenotype.

Movement of solutes across a plasma membrane requiring the addition of energy

Active Transport

Post-transcrptional mRNA processing

Alternative RNA gene splicing

24) Which structure is NOT part of the endomembrane system? A) nuclear envelope B) chloroplast C) Golgi apparatus D) plasma membrane

isomers are two or more molecules with ___ chemical formula and ___ molecular structures.

the same different

Why CA why unicellular

things go from simple to complex org start at small

Convection-

transfer of heat by movement of air or liquid past surfaces, breese = heat lost

Transformation, Transduction and COnjugation-

transformation- bacteria take in plasmids from environment transduction- bacteria acquire new DNA from phage conjugation- bacteria exchange DNA through direct connection, pilus attaches and forms a mating bridge...directly transfer (must have F factor)

Bacteria and protozoans are ___.

unicellular organisms

The tertiary structure of a protein is the

unique three-dimensional shape of the fully folded polypeptide.

factors that allow adaptive radiation

vacant niches // adaptive radiation or other organisms used for food // some sort of evolutionary innovation // population of area with few competitors

Which of the following may form between any closely aligned molecules?

van der Waals interactions

hydrophilic

water loving

Which of the following is a hydrophobic material?

wax

One of the key innovations in the evolution of eukaryotes from a prokaryotic ancestor is the endomembrane system. What eukaryotic organelles or features might have evolved as a part of, or as an elaboration of, the endomembrane system?

nuclear envelope

RNA

nucleic acid

a gene

nucleic acid

Which of the following correctly lists the order in which cellular components will be found in the pellet when homogenized cells are treated with increasingly rapid spins in a centrifuge?

nucleus, mitochondria, ribosomes

end result of oogenesis

one ovum (haploid)

Plant and animal cells differ mostly in that

only plant cells have cell walls

Which of the following processes includes all others?

passive transport

the linkage commonly found between amino acids in a chain of amino acids is called a ___ bond.

peptide

Linkages between the monomers of proteins

peptide bond

Which cell would be best for studying lysosomes?

phagocytic white blood cell

answer to 15:

polar covalent bonds

The polar covalent bonds of water molecules

promote the formation of hydrogen bonds.

MTOC's migrate to opposite poles

prophase

size euks vs pros

pros- .5-5 um euks- 10-100 um

In alcohol fermentation, NAD+ is regenerated from NADH by

reduction of acetaldehyde to ethanol (ethyl alcohol).

autocrine pathway-

secreted molecules diffuse locally and response in cells that secrete Ex: tumor and immune cells

paracrine pathway-

secreted molecules diffuse locally and trigger resp in neighboring cells ex: developing and embryogensis

correct order of structures from when sperm pass to when ejaculation produces

seminiferous tubules, epididymis, vas deferens, urethra

A primary objective of cell fractionation is to

separate the major organelles so that their particular functions can be determined

pituitary gland

serves as an interface between the nervous and endocrine systems

Thermogenesis

shivering

gametic isolation

sperm of one species may not be able to fertilize egg of another species because sperm may not be able to survive in reproductive tract, may not be able to fertilize egg, etc

When oxygen is released as a result of photosynthesis, it is a direct by-product of

splitting water molecules.

Plants store most of their energy for later use as

starch

A burn from steam at 100 degrees C is more severe than a burn from boiling water because

steam releases a great deal of heat as it condenses on the skin

epinephrine

stimulate immediate fight or flight reactions, produced by the medulla

glucagon

stimulates liver to release glucose, produced by the pancreas

Where does the Calvin cycle take place?

stroma of the chloroplast

homologous structures

structures in different species that are similar because of common ancestry (ex. whale flipper & bat wing)

What is taxonomy?

study of classification that attempts to reflect relatedness names and groupings are continuously revised with new data

Cytokinesis Begins

telophase

Each element has its own characteristic atom in which

the atomic number is constant

Most CO2 from catabolism is released during

the citric acid cycle.

Hydrolysis is involved in which of the following?

the digestion of sucrose, a disaccharide to its monomers of glucose and fructose

The chemical group that can cause an organic molecule to act as a base is

-NH2

In addition to the ABO blood groups, humans have an MN blood type system in which the M and N alleles are co-dominant to one another. A group of scientists found that in one population the frequency of the M allele was 0.82, and the frequency of the N allele was 0.18. Assuming that the population is in Hardy‑Weinberg equilibrium, which of the following is the expected frequency of individuals with the genotype MN?

0.295

Water Soluble PAthway-

1. binding of molecule to recpetor...response (enzyme is activated ) 2. chnages from extracellular to intra cell...signal transduction ex: fight or flight 1. kidneys secrete epinephrin 2. epin binds to G pro 3. cascade of events, cAMP synthesis 4. act of protein kinase A leads to activ of enzyme for glycogen breakdown...release glucose

If there are 20 chromatids in a cell, how many centromeres are there?

what is te difference between the number of H+ ions in a solution witha pH of 2 compared with a solution at a pH of 6?

10,000

A sodium ion (Na+) contains 10 electrons, 11 protons, and 12 neutrons. What is the atomic number of sodium?

The students plan to use a significance level of p=0.01. Which of the following is the most appropriate critical value for the students to use in their chi-square goodness-of-fit test?

11.34

Which molecule has both hydrophilic and hydrophobic properties and would be found in plasma membranes?

Which of the following molecules contains a glycosidic linkage type of covalent bond?

If a cell has 8 chromosomes at metaphase of mitosis, how many chromosomes will it have during anaphase?

A cell containing 92 chromatids at metaphase of mitosis would, at its completion, produce two nuclei each containing how many chromosomes?

12. Which of the following correctly describes a possible sex genotype of an organism? a. XX b. AaBbCC c. Alive d. Dead e. Orange

13. Crossing an organism with the genotype Aa with an organism with the same genotype (Aa) yields what ratio of genotypes? a. 1:2:1 b. 3:1 c. 1:1 d. 1 e. 0

Cross-link in protein

A cross-link is a bond that links one polymer chain to another. They can be covalent bonds or ionic bonds.

Which of the following steps is a signaling pathway typically occurred first once a chemical messenger reaches a target cell?

A ligand binds to a receptor.

A scientist wishes to provide experimental evidence to support the model shown in Figure 1 by demonstrating the ability to synthesize an RNA molecule. Which of the following is an alternative hypothesis that can be tested to support the RNA World Hypothesis?

A mixture of ribonucleotides such as adenine and uracil will spontaneously form single-stranded chains of RNA .

Based on the model, which of the following statements best explains an enzymes specificity for a particular substrate molecule?

A molecule with negative charges interacts with positively charged side chains in the enzymes active site.

Which of the following best describes the process that adds a monosaccharide to an existing polysaccharide?

A specific enzyme removes the hydrogen ( H ) from the monosaccharide and the hydroxide ( OH ) from the polysaccharide, creating a bond between the two and creating a water ( H2O ) molecule. -This is a description of dehydration synthesis, which joins multiple monosaccharides to create a polysaccharide and produces water (H2O) molecules.

Fertilization normally

A) Reinstates diploidy

Which of the following describes what happens as a chlorophyll pigment absorbs energy from sunlight?

An electron moves to a higher electron shell and the electron's potential energy increases.

Which of the following statements best justifies the claim that changes in the expression of ced -9 in C. elegans can affect regulation of apoptosis in the cell?

An experiment showed that a mutation in the ced -9 gene led to excessive cell death in C. elegans.

Cholesterol is a naturally occurring substance that helps regulate the fluidity of a cell's plasma membrane. A cholesterol molecule can be represented as having a polar head and a nonpolar region, as shown in the figure. Which of the following models shows how cholesterol molecules most likely interact with the phospholipid bilayer of a cell's plasma membrane?

Answer D Correct. The model correctly shows the polar heads of the cholesterol molecules interacting with the polar heads of the phospholipids. Also, the model correctly shows the nonpolar regions of the cholesterol molecules interacting with the hydrophobic interior of the phospholipid bilayer.

What term defines chromosomes that are not sex chromosomes? A. Karyotypes B. Pedigrees C. Autosomes D. Dominant alleles

Autosomes

14. Crossing an organism with the genotype Aa with an organism with the same genotype (Aa) yields what ratio of phenotypes? a. 1:2:1 b. 3:1 c. 1:1 d. 1 e. 0

18. A blue plant is crossed with a red plant. Their offspring is purple. What is this an example of? a. Codominance b. Incomplete Dominance c. Corecessive d. Incomplete Recessive e. None of the above

Gender identity is when children begin to do which of the following? (A) Believe that gender is consistent over the life span (B) Identify as either male, female, or some blend of male and female (C) Believe that there are set ways that people of different genders are supposed to behave (D) Make generalizations about a gender group (E) Develop a way of thinking about people of each gender

The somatic cells derived from a single-celled zygote divide by which process?

B) mitosis

8. Which of the following pairs of alleles shows a homozygous recessive pair? a. XX b. Xx c. xx d. All of the above e. None of the above

A population of 250 birds inhabit the canopy of a tropical rain forest that has a carrying capacity of 400 birds. What is the maximum population growth rate (rmax) if the population grows to 283 in one year?

C. 0.35

Which of the following molecules would you predict is capable of forming hydrogen bonds?

CH4O

Which of the following categories includes all the others in the list?

Carbohydrate

Which of the following statements regarding carbon is false?

Carbon has the capacity to form polar covalent bonds with hydrogen

tRNA

Carries amino acids from the cytoplasmic pool of amino acids to mRNA at the ribosome

Vector

Carries the recombinant DNA molecule, DNA carrier of segment to be cloned

Some cells, such as intestinal cells, exchange a lot of material with their surroundings. The surface-to-volume ratio of these cells affects the efficiency of material exchange. The table provides measurements of four different eukaryotic cells. Cell1234Total surface area (μm2)406080100Total volume (μm3)20103020 Based on the data, which cell is likely to be most effective in the exchange of materials?

Cell 4

Which of the following justifies the claim that differences in components of cell signaling pathways explain the different responses to epinephrine?

Cell signaling depends on the ability to detect a signal molecule...

Based on the phylogenetic relationships shown in Figure 1, which of the following best explains the similarities exhibited by whales, bony fishes, and cartilaginous fishes?

Convergent evolution, because these organisms do not share a recent common ancestor.

1. Meiosis creates how many functional daughter cells in females? a. 1 b. 2 c. 3 d. 4 e. None of the above

29. A person's blood type is an example of what? a. Continuous Generations b. Discontinuous Generations c. Continuous Variation d. Discontinuous Variation e. None of the above

Which of the following best predicts the effect of the chromosomal segregation error shown in Figure 5-7? A) All of the resulting gametes will have an extra chromosome. B) All of the resulting gametes will be missing a chromosome. C) Half of the resulting gametes will have an extra chromosome and the other half will be missing a chromosome. D) Half of the resulting gametes will have the correct number of chromosomes, and the other half will have an incorrect number of chromosomes.

D) Half of the resulting gametes will have the correct number of chromosomes, and the other half will have an incorrect number of chromosomes.

Figure 1 shows a short segment of a double-stranded nucleic acid molecule. Figure 1. A short segment of a double-stranded nucleic acid molecule Which of the following statements is correct about the molecule shown in Figure 1 ?

D. It is DNA because of the nucleotides present.

Which of the following graphs best predicts the data collected during the experiment?

D. Up, Medium, Up

cDNA

DNA produced by retroviruses using the enzyme reverse transcriptase

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?

Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers.

Based on the information in Figure 1, which type of mutation explains the nature of the change in DNA that resulted in cystic fibrosis in the affected individual?

Deletion, because a thymine is missing, which changes the reading frame.

The main goals of the Human Genome Project include all of the following except A. developing mutations of all human genes. B. sequencing the genomes of model organisms to help interpret human DNA. C. identifying all human genes. D. sequencing all 3 billion base pairs of human DNA.

Developing mutations of all human genes.

What is a karyotype?

E) A display of every pair of homologous chromosomes within a cell, organized according to size and shape

Asexual reproduction and sexual reproduction differ in all but which of the following ways?

E) Asexual reproduction is utilized only by fungi and protists, whereas sexual reproduction is utilized only by plants and animals.

The cyclin component of MPF is destroyed toward the end of this phase:

E) M

During which phases of mitosis are chromosomes composed of two chromatids?

E) from G2 of interphase through metaphase

Gregor Mendel contributed to genetic theory by concluding all of the following except A. each adult has six copies of each gene. B. inheritance is determined by genes. C. alleles for each gene usually segregate independently of each other. D. alleles may be dominant or recessive

Each adult has six copies of each gene

1) Load samples into wells 2) Apply electrical current 3) View separated bonds

Electrophoresis steps

According to the fluid Mosaic model of membrane structure proteins of the membrane are mostly

Embedded in a lipid bilayer

After double fertilization with an XX and XY, what would be the genotypes of the embryos and endosperm nuclei?

Embryo XX and endosperm XXX or embryo XY and endosperm XXY

Cleavage, gastrulation, organogenesis

Embryonic development stages

A researcher claims that the initial rise of oxygen in Earth's early atmosphere, which occurred approximately 2.3 billion years ago, resulted from the metabolic activity of prokaryotic organisms. The claim is based on an interpretation of the geochemical and fossil evidence represented in Figure 1. Which of the following types of evidence will best support the researcher's claim?

Evidence that the cyanobacteria produced oxygen as a by-product of photosynthesis

Mendel found that the generation between the P and F2 generation is fundamental to genetic theory. What is the generation between the P and F2 generations called? A. P2 B. F1 C. F0 D. P3

Based on the results of the experiment, which of the following statements best predicts the effect of urea on the enzymes function?

Function will be disrupted by adding the urea and regained by removing the urea.

Chemical bonds that are formed when one atom with a partial positive charge (created from unequal sharing of electrons) is electrically attracted to another atom with a partial negative charge (also created from unequal sharing of electrons) are called ___.

Hydrogen bonds

Nucleotide base pairing in DNA is universal across organisms. Each pair (T−A; C−G) consists of a purine and a pyrimidine. Which of the following best explains how the base pairs form?

Hydrogen bonds join a double-ringed structure to a single-ringed structure in each pair.

Some viral infections can lead to the rupture of the lysosome membrane. Which prediction of the effect of this disruption of cellular compartmentalization is most likely correct?

Hydrolytic enzymes will be released, which will cause cell death.

If the pH of a solution is decreased from 7 to 6, it means that the concentration of

H⁺ has increased 10 times what it was at pH 7

aldehyde

If the carbonyl group is at the end of the carbon skeleton

The major class of biological molecules that are not polymers

Lipids

Connective Tissue Loose and Dense-

Loose- binds cells to epithelia to underlying tissue ex: skin or adipose--fat, insulates Dense- fibrous, dense arrangement of parallel collagenous fibers (tendons and ligaments)

Which of the following best explains how the sweet pea plants in the parental generation produce F1 offspring with 14 chromosomes?

Meiosis 2 and 3 lead to the formation of cells with 7 chromosomes. During meiosis II, homologous chromosomes separate. During meiosis IIII, sister chromatids separate. Two cells combine during fertilization to produce offspring with 14 chromosomes.

5' cap

Methyl cap,helps mRNA move through nuclear pore and attach to ribosome

Which of the following observations best supports the claim that mitochondria evolved from once-free-living prokaryotic cells by the process of endocytosis?

Mitochondria are surrounded by a double membrane.

What is used to determine one's maternal ancestry? A. Mitochondrial DNA B. Ribosomal DNA C. Transfer RNA D. Messenger RNA

Mitochondrial DNA

5 Kingdoms and why it changed...

Monera (prokaryotes), protista(unicell orgs), plantae, fungi and animalia *highlighted two types of cells *separated euks and pros BUT... some prokaryotes differas much from each other as from eukaryotes SO 3 DOMAINS

Monoparaphyletic, Paraphyletic and Polyphletic-

Mono- consists of ancestral species and all descendants Para-ancestral species and some descendants, CA is part Poly- includes distantly related species but not CA

Silent mutation

Mutations in DNA that do not significantly alter the phenotype of the organism in which they occur

Which of the following sets of data provides evidence that best supports common ancestry for organisms in all three domains?

Organisms in Bacteria, Archaea, and Eukarya each have adenine, thymine, guanine, and cytosine bases forming their DNA.

Figure 10.1 shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Why are they different?

Other pigments absorb light in addition to chlorophyll a.

The final electron acceptor of the electron transport chain thst functions in aerobic oxidative phosphorylation is

Oxygen

1) denaturation 2) Annealing of primers 3) Synthesis

PCR steps

Three living species X Y Z share a common ancestor T, as do extinct species U and V. A grouping that includes species T, X,Y, and Z makes up a...

Paraphyletic group

What is a legal tool that gives an individual or company the exclusive right to profit from its innovations for a number of years? A. Clone B. Gene map C. Pedigree D. Patent

Patent

What term identifies the chart that can be used to analyze the pattern of inheritance followed by a particular trait? A. Autosome B. Karyotype C. Pedigree D. Codominance

Pedigree

Because cheetahs, Acinonyx jubatus, experienced a bottleneck event about ten thousand years ago, living cheetahs exhibit very little genetic variation compared to other living species of large cats. Which of the following principles best justifies a claim that cheetahs, compared to other large cats, have a relatively low resilience to environmental perturbations?

Populations with little genetic diversity are less likely to contain individuals that can withstand different selective pressures.

The structural level of a protein least affected by a disruption in hydrogen bonding is the

Primary level

A _________ of genetically modified crops is that many of them produce higher yields, reducing the amount of land and other resources devoted to agriculture. A. restriction B. pro C. discrimination D. con

Pro

1.What term best defines the likelihood that a particular event will occur? A. Probability B. Accuracy C. Segregation D. Average

Probability

Transduction

Process by which DNA is transferred from one bacterium to another by a virus, phage viruses that contain bits of bacterial DNA as they infect one cell

Which of the following best explains how the pattern of DNA arrangement in chromosomes could be used, in most cases, to determine if an organism was a prokaryote or a eukaryote?

Prokaryotic DNA - Single circular chromosome Eukaryotic DNA - Multiple linear chromosomes

The Plasma membrane consists principally of

Protiens embedded in a phospholipid bilayer

All of the following are characteristics of Punnett squares except A. Punnett squares are used only to predict homozygous combinations. B. Punnett squares are used to predict phenotype combinations in genetic crosses. C. Punnett squares follow the principle of segregation. D. Punnett squares are used to predict genotype combinations in genetic crosses.

Punnett squares are used only to predict homozygous combinations.

Scientists sometimes use radiation and chemicals when engaging in selective breeding, a form of biotechnology. What purpose does the use of radiation serve? A. Radiation induces hybridization. B. Radiation induces inbreeding. C. Radiation induces mutations. D. Radiation induces polyploidy.

Radiation induces mutations.

Based on the figure which of the following statements best describes the relationship between regions 1 and 2 of the protein?

Region 1 is hydrophilic because it interacts with an aqueous environment, whereas region 2 is hydrophobic because it interacts with the interior of the membrane.

Based on the figure, which of the following statements best describes the relationship between regions 1 and 2 of the protein?

Region 1 is hydrophilic because it interacts with an aqueous environment, whereas region 2 is hydrophobic because it interacts with the interior of the membrane.

A group of researchers claim that chance events play an important role in the evolution of populations. To test their claim, they monitored 12 populations of E. coli for 10,000 generations under the same environmental conditions. They found that although all 12 populations were exposed to the same environmental pressures, each population had differentiated from one another genetically after 10,000 generations. Which of the following statements includes a reasonable refinement that researchers could use in repeating the experiment?

Start each population with genetically identical bacterial cells from a single culture to make sure that the initial genetic variation in all of the populations was exactly the same.

Based on the model presented in figure 1, which of the following changes will most likely result from a depletion of available ATP stores inside the cell?

The Na+ concentration inside the cell will increase.

The experiment can be repeated with guaiacol, which will reveal the effect of guaiacol on the reaction rates.

The label on a container of margarine lists "hydrogenated vegetable oil" as the major ingredient. What is the result of adding hydrogens to vegetable oil?

The hydrogenated vegetable oil stays solid at room temperature.

Transcription

The info in DNA sequence is copied into complementary RNA sequence

Which of the following changes in the FGFR signaling pathway is most likely to result in uncontrolled cell proliferation?

The irreversible association of FGFR proteins.

Which of the following statements best represents the relationships between the light reactions and the Calvin cycle?

The light reactions provide ATP and NADPH to the Calvin cycle, and the cycle returns ADP, mc016-1.jpgi, and NADP+ to the light reactions.

Which of the following best explains the divergence in morphology in the birds?

The original habitat had many available unoccupied ecological niches that were colonized by populations of the original species.

When electrons flow along the electron transport chains of mitochondria, which of the following changes occurs?

The pH of the matrix increases.

Enzymes that break down DNA catalyze the hydrolysis of the covalent bonds that join nucleotides together. What would happen to DNA molecules treated with these enzymes?

The phosphodiester linkages of the polynucleotide backbone would be broken.

What is an example of transport across a membrane requires energy

The removal of waste from a central vacuole by exocytosis

What would be the probable effect of adding more product to a reaction that is in equilibrium?

The reverse reaction would increase and more reactants would be formed.

Which of the following best predicts what will happen when a normal cell is exposed to a retrovirus?

The reverse transcriptase will produce DNA from the viral RNA, which can be incorporated into the host's genome and then transcribed and translated.

E area on ribosome

The ribosomal site harbouring decylated tRNA on transit out from the ribosome. Exit

A area on ribosome

The ribosomal site most frequently occupied by aminoacyl-tRNA. Arrival, mRNA binds to small unit of ribosome 1st

Which of the following statements best predicts the effect of a loss of function of the insulin receptor's intracellular domain?

The storage of GLUT4 in vesicles inside the cell will increase.

The total system that includes photosynthetic organisms and the Sun becomes less ordered over time.

Which of the following transport mechanisms will be affected most directly by a temporary shortage of ATP molecules inside the cell?

The transport of GLUCOSE molecules against a concentration gradient.

Which of the following transport mechanisms will be affected most directly by a temporary shortage of ATP molecules inside the cell?

The transport of glucose molecules against a concentration gradient

Inducible operon

Their default state is "off", meaning that binding of the active regulator protein to DNA, thereby blocking transcription initiation, is the default state. Lac

Which of the following questions would be most useful to researchers trying to determine the role of meiosis in the F2 phenotypic frequencies?

What is the recombination frequency between the genes for petal shape and pollen shape?

Beetroot cells contain a family of dark red pigments called betalains. The selectively permeable nature of the beetroot cells keeps the internal environment of the cell separate from the external environment of the cell. Researchers are interested in determining whether the selective permeability of beetroot cells is due to the cell membrane or if it is due to the cell wall. Exposure to cellulase is known to damage the structure of the cell wall. An experiment is set up in which beetroot cells are placed in an aqueous solution with cellulase and in one without cellulase. Which of the following results best refutes the alternative hypothesis that selective permeability is a consequence of the cell wall?

When beetroot cells are placed in a solution with cellulase, the solution remains clear.

Which of the following evidence best supports a claim that tryptophan functions as a corepressor?

When trpR is mutated, the trp operon is transcribed regardless of tryptophan levels.

climates tend to be moderate near large bodies of water because

a large amount of solar heat is absorbed during the gradual rise in temperature of the water, water releases heat to the environment as it cools, the high specific heat of water helps to moderate air temperatures, and a great deal of heat is absorbed and released as hydrogen bonds break or form.

Why is comparing DNA in orgs challenging?

after sequencing, must allign if species are very closely related, differ at one or fewer sites not closely related, diff bases at many sites and diff lengths a certain non coding DNA seq near spec gene are very sim in two species but base in one has been deleted....frameshift. technology to estimate better alignment

How are bacteria able to carry out photosynthesis and aerobic respiration without organelles?

anaer resp- use sulfate or nitrate as last electron accept take atmo nitrogen to make amino acids and organic molecules, just need light, CO2 and nitrogen

Protiens to be used within the cytosol are generally synthesized

by free ribosomes

The lowest level of biological organization that can survive and reproduce is the ___.

cell

order of events in natural selection

change in environment => poorly adapted organisms die out => well adapted organisms survive and reproduce => change in allele frequency

Lamarck's Theory of Evolution

changes organisms acquired in their lifetime could be passed down to their offspring

Emergent properties are

characteristics that depend on the level of organization of matter but do not exist at lower levels of organization

Speed and Duration in Endo vs. Nervous

endo- seconds nerv- fraction of sec

disruptive selection

favors variants at both ends of distribution

Conjugation-

horiz, bacteria exchange DNA through direct connection

Even though plants carry on photosynthesis, plant cells still use their mitochondria for oxidation of pyruvate. When and where will this occur?

in all cells all the time

In a normal cellular protein, where would you expect to find a hydrophobic amino acid like valine?

in the interior of the folded protein, away from water, or in a transmembrane portion interacting with lipid fatty acid chains

Disaccharides can differ from each other in all of the following ways except

in the number of their monosaccharides.

Lipid-soluble signaling molecules, such as testosterone, cross the membranes of all cells but affect only target cells because __________.

intracellular receptors are present only in target cells

what does it mean to "silence" a gene and what causes this to happen

loss of gene expression from mutation

Convergent evolution-

occurs when similar environmental pressures and NS produce similar (analogous) adaptations in orgs from diff env lineages

mechanical isolation

prezygotic mechanism // involves morphological differences that prevent successful mating

Which of the following are directly associated with photosystem I?

receiving electrons from the thylakoid membrane electron transport chain

A biologist wants specifically to examine the surfaces of different types of cells in kidney tubules of small mammals. The cells in question can be distinguished by external shape, size, and 3-D characteristics. Which of the following would be the optimum method for her study?

scanning electron microscopy

Neuroendocrine PAthway-

sensory neurons respond to stimulus, send impules to nero secreting cells...secretion of neurohormone and binds to receptor es: oxytocin: regulation of milk in nursing, suckling infant stim sensory neuron in nipple, generates signal in nervous system sent to hypothalamus.....triggers realease of oxytocin, milk secretion

female Bobolinks tend to choose males who sing a familiar song. this is an example of

sexual selection

Evaporative cooling is a result of

the absorption of heat as hydrogen bonds break and the reduction in the average kinetic energy of a liquid after energetic water molecules enter the gaseous state.

What other evidence could you use to analyze evolutionary relatedness among gibbons, monkeys, and humans?

the amino acid sequences of other proteins from gibbons, monkeys ad humans

which statement best describes the observed relationship between atmospheric CO2 enrichment and plant growth under ideal and stressed conditions? -In ideal conditions: standard CO2 environment (400 ppm CO2) or in an enriched CO2 environment (700 ppm) plants grew more while in stressed conditions plants did not -measured by total dry weight of plant per g

the increase in atmospheric CO2 resulted in a greater increase in plant growth under stressed conditions than under ideal conditions.

which of the following possibilities can be measured to estimate an organisms evolutionary fitness

the number of offspring it produces over its lifetime that survive to breed

Monkeys and humans share many of the same DNA sequences and have similar proteins, indicating that

the two groups share a relatively recent common ancestor.

Significance of prokaryote/eukaryote dividng line-

true nucleus eukaryotes have a nuclear envelope and membrane enclosed DNA, leads to more modification

How are the electrons of an oxygen atom arranged?

two in the 1s orbital, two in both the 2s and 2px orbitals, and one each in the 2py and 2pz orbitals, creating a valence of two.

Which organelle often takes up much of the volume of a plant cell?

vacuole

correct order of structure from when sperm pass to when egg fertilizes

vagina, cervix, uterus, oviduct

what must be present for natural selection to act on population

variation of individuals in population

Transgenic animal cells are formed through the transformation of animal cells. Steps in this process are correctly described in all of following except A. DNA molecules used for transformation contain genetic markers. B. Enzymes help insert foreign DNA into the chromosomes of an injected cell. C. DNA is injected directly into the nucleus of animal cells. D. Agrobacterium inserts DNA plasmids.

Agrobacterium inserts DNA plasmids.

The secondary structure of proteins

Alpha helix

Which chemical group is most likely to be responsible for an organic molecule behaving as a base?

Amino

Cells that are in a nondividing state are in which phase?

A) G0

Nerve and muscle cells are in this phase:

A) G0

Which of the following statements best helps justify the inclusion of group 2 as one of the controls in the experiment based on Table 3-2? A) It will show whether the changes observed in group 1 depend on the metabolic activity of soil bacteria. B) It will show whether the changes observed in group 1 depend on the type of plants used in the experiment. C) It will show the average growth rate of seedlings that are maintained in a nonsterile environment. D) It will show the changes that occur in the roots of seedlings following an infection by soil bacteria.

A) It will show whether the changes observed in group 1 depend on the metabolic activity of soil bacteria.

Why is water such an excellent solvent?

As a polar molecule, it can surround and dissolve ionic and polar molecules

Water is an excellent solent. Select te property that justifies this statement.

As a polar molecule, it can surround and dissolve ionic and polar molecules.

A researcher claims that only a portion of the light energy captured by green plants is available for growth and repair. Which of the following observations best helps justify the researcher's claim?

As light energy is converted to chemical energy by metabolic processes, some of the energy is lost as heat.

Which of the following is an example of a key element of Jean Piaget's theory of cognitive development? (A) Stephani's reading progressed the same from seventh grade to eighth grade as it did from first grade to second grade. (B) Catherine finally realized her grandfather is her father's father. (C) Erin excelled at math despite the fact that she did not have good math teachers. (D) Courtney's ability to read was equally influenced by all the books in her home and her age. (E) Spencer's vocabulary increased by the same number of words every ten years throughout his life.

Which of the graphs below best represents the predicted change in mass over time of the dialysis bag in the beaker to which albumin was added?

Most cells that have become transformed into cancer cells have which of the following characteristics when compared to normal, healthy cells? A. Shorter cell cycles B. More carefully regulated rates of cell division C. Lower rates of mitosis D. Higher rates of protein translation E. Identical DNA

A. Shorter cell cycles

The light reactions of photosynthesis supply the Calvin Cycle with

ATP and NADPH

Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle?

ATP and NADPH

A researcher claims that the synthesis of ATP from ADP and inorganic phosphate (Pi) is essential to cellular function. Which of the following statements best helps justify the researcher's claim?

ATP hydrolysis is an energy-releasing reaction that is often coupled with reactions that require an input of energy.

Muscle contraction depends on ATP hydrolysis. During periods of intense exercise, muscle cells rely on the ATP supplied by three metabolic pathways: glycolysis, mitochondrial respiration, and the phosphagen system. Figure 1 shows the rates at which the three metabolic pathways produce ATP following the start of an intense period of exercise. Which of the following correctly uses the data to justify the claim that the phosphagen system is an immediate, short-term source of ATP for muscle cells?

ATP production by the phosphagen system increases and decreases rapidly following the start of the exercise period.

A researcher claims that a certain herbicide suppresses plant growth by inhibiting chloroplast function. To test the claim, the researcher treats isolated chloroplasts with increasing concentrations of the herbicide. The data from the experiment are presented in Table 1. Which of the following statements best clarifies how the data support the researcher's claim?

ATP synthase activity depends on a proton gradient across the thylakoid membrane.

PCR

Accelerate pace of genetic engineering by quickly creating many clones of DNA sequence without plasmid

Some substances can pass through an actual cell membrane much faster than they passed through the artificial membrane in this study. Which of the following statements best explains this finding?

Actual cell membranes have a variety of proteins embedded in the membrane that are absent in the artificial membrane.

Some substances can pass through there an actual cell membrane much faster than they passed through the artificial membrane in the study. Which of the following statements best explains the findings?

Actual cell membranes have a variety of proteins embedded in the membrane that are absent in the artificial membrane.

Based on Table 5-8, the mean number of fruit flies per student that are homozygous recessive for both genes is closest to which of the following? A) 89.75 B) 29.0 C) 22.75 D) 18.5

B) 29.0

B) 3

Density-dependent inhibition is explained by which of the following?

B) As cells become more numerous, the cell surface proteins of one cell contact the adjoining cells and they stop dividing.

What triggers the cell's passage past the G2 checkpoint into mitosis?

B) MPF

Which term describes centromeres uncoupling, sister chromatids separating, and the two new chromosomes moving to opposite poles of the cell?

B) anaphase

If mammalian cells receive a go-ahead signal at the G1 checkpoint, they will

B) complete the cycle and divide.

Figure 1. Diversity of macroscopic invertebrates in different stream types. Error bars represent a 95% confidence interval (±two Standard Errors from the mean). Which of the stream types had a statistically lower macroscopic invertebrate species diversity than the seasonal streams?

B. Intermittent streams only

Figure 1. Comparison of observations of selected mammals in 1996 and 2011. Figure 2. Change in host preference by Culex cedecei between 1979 and 2016.

B. Python predation has caused a trophic cascade that changed the mosquitoes' niche.

Which of the following describes how the vent bacteria harvest energy to produce organic compounds for use by the vent community?

B. The bacteria function as chemoautotrophs, extracting energy from hydrogen-rich inorganic molecules.

Figure 1. Plant species richness in lightly and heavily grazed savanna communities. Which of the following best predicts the results of a drought in the savanna research area with regards to community resilience to this environmental change?

B. The lightly grazed area is likely to recover more quickly from the drought due to greater biodiversity.

A fish population of 250 in a pond has a maximum annual rate of increase of 0.8. If the carrying capacity of the pond is 1,500 for this species, what is the expected population size after one year?

B. 417

Point mutation

Base-pair substitution

Initiation of transcription

Begins when RNA polymerase recognizes and binds to DNA at promoter, once attached and transcription factors bound, transcription of DNA template begins

Enhancing

Binding of activator protein, stimulates transcription to occur faster

Repressor protein

Binds to regulatory sites on DNA (operators) to prevent/ decrease initiation of transcription, allosteric regulation

Figure 1. Molecule 1 represents RNA, and molecule 2 represents DNA. Which of the following best describes a structural similarity between the two molecules shown in Figure 1 that is relevant to their function?

Both molecules contain nucleotides that form base pairs with other nucleotides, which allows each molecule to act as a template in the synthesis of other nucleic acid molecules.

Which of the following best explains the trend shown in Figure 1? (Kentucky Derby)

By 1940, most genetic variation for speed had been lost from the gene pool.

Which of the following mechanisms do the water molecules most likely move into the large intestine?

By PASSIVE transport from an area of LOW osmolarity to an area of HIGH osmolarity.

20) The nuclear lamina is an array of filaments on the inner side of the nuclear membrane. If a method were found that could cause the lamina to fall into disarray, what would you most likely expect to be the immediate consequence? A) the loss of all nuclear function B) the inability of the nucleus to divide during cell division C) a change in the shape of the nucleus D) failure of chromosomes to carry genetic information

26. Which of the following is heavily influenced by environmental influences? a. Continuous Generations b. Discontinuous Generations c. Continuous Variation d. Discontinuous Variation e. None of the above

52) Which of the following statements about the cytoskeleton is true? A) The cytoskeleton of eukaryotes is a static structure most resembling scaffolding used at construction sites. B) Although microtubules are common within a cell, actin filaments are rarely found outside of the nucleus. C) Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other. D) Chemicals that block the assembly of the cytoskeleton would have little effect on a cell's response to external stimuli.

54) A mutation that disrupts the ability of an animal cell to add polysaccharide modifications to proteins would most likely cause defects in its _____. A) nuclear matrix and extracellular matrix B) mitochondria and Golgi apparatus C) Golgi apparatus and extracellular matrix D) nuclear pores and secretory vesicles

8) Cell size is limited by _____. A) the number of proteins within the plasma membrane B) the surface area of mitochondria in the cytoplasm C) surface to volume ratios D) the size of the endomembrane system

At which bond would water need to be added to achieve hydrolysis of the peptide, back to its component amino acids?

Carol Gilligan was critical of Lawrence Kohlberg's theory of moral development. What is the basis of her critique? (A) She thought he should have used more men in his study. (B) She thought he should have conducted actual experiments. (C) She thought his findings about men are not generalizable to women. (D) She thought his research was unethical. (E) She thought he should have only studied adolescents.

Which of the following best represents two different signaling pathways that share a second messenger?

Figure 1-1 represents a segment of DNA. Radiation can damage the nucleotides in a DNA molecule. To repair some types of damage, a single nucleotide can be removed from a DNA molecule and replaced with an undamaged nucleotide. Which of the four labeled bonds in Figure 1-1 could be broken to remove and replace the cytosine nucleotide without affecting the biological information coded in the DNA molecule? A) Bond X only B) Bond W only C) Bonds Y and Z at the same time D) Bonds W and Z at the same time

C) Bonds Y and Z at the same time

Which of the following best describes a structural similarity between the two molecules shown in Figure 1-10 that is relevant to their function? A) Both molecules are composed of the same four nucleotides, which allows each molecule to be produced from the same pool of available nucleotides. B) Both molecules are composed of the same type of five-carbon sugar, which allows each molecule to act as a building block for the production of polysaccharides. C) Both molecules contain nucleotides that form base pairs with other nucleotides, which allows each molecule to act as a template in the synthesis of other nucleic acid molecules. D) Both molecules contain nitrogenous bases and phosphate groups, which allows each molecule to be used as a monomer in the synthesis of proteins and lipids.

C) Both molecules contain nucleotides that form base pairs with other nucleotides, which allows each molecule to act as a template in the synthesis of other nucleic acid molecules.

The tadpoles of Mexican spadefoot toads are known to exhibit phenotypic plasticity depending on food availability. Tadpole mouthparts can vary significantly, prompting researchers to categorize them as either omnivore-morph or carnivore-morph. Carnivore-morph tadpoles are larger and have mouthparts that are better suited for predation. Remarkably, carnivore-morph tadpoles can change into omnivore-morph tadpoles when the food supply changes. Which of the following best describes an advantage of the phenotypic plasticity displayed by the tadpoles? A) It allows the tadpoles to change their genome in response to environmental pressures. B) It enables the tadpoles to develop into a distinct species of toads. C) It gives the tadpoles increased versatility with respect to diet. D) It allows the tadpoles to delay metamorphosis until there is maximal food available for the adults.

C) It gives the tadpoles increased versatility with respect to diet.

Based on Table 3-3, which of the following statements best helps justify the inclusion of test tube 5 in the experiment? A) It will act as a control for test tube 4 by showing the effect of the presence or absence of a substrate B) It will act as a control for test tube 4 by showing the effect of a change in environmental temperature C) It will act as a control for test tube 6 by showing the effect of the presence or absence of the enzyme. D) It will act as a control for test tube 6 by showing the effect of a change in sodium chloride concentration.

C) It will act as a control for test tube 6 by showing the effect of the presence or absence of the enzyme.

Based on Figure 1-4, which statement best describes the observed relationship between atmospheric CO2 enrichment and plant growth under ideal and stressed conditions? A) The increase in atmospheric CO2 had no observable effect on plant growth under either ideal or stressed conditions. B) The increase in atmospheric CO2 resulted in a greater increase in plant growth under ideal conditions than under stressed conditions. C) The increase in atmospheric CO2 resulted in a greater increase in plant growth under stressed conditions than under ideal conditions. D) The increase in atmospheric CO2 resulted in an inhibition of plant growth under both ideal and stressed conditions.

C) The increase in atmospheric CO2 resulted in a greater increase in plant growth under stressed conditions than under ideal conditions.

Nucleotides can be radiolabeled before they are incorporated into newly forming DNA and can therefore be assayed to track their incorporation. In a set of experiments, a student-faculty research team used labeled T nucleotides and introduced these into the culture of dividing human cells at specific times. The research team used the setup to study the incorporation of labeled nucleotides into a culture of lymphocytes and found that the lymphocytes incorporated the labeled nucleotide at a significantly higher level after a pathogen was introduced into the culture. They concluded that

C) infection causes lymphocytes to divide more rapidly.

Figure 1. Gel electrophoresis of three prepared samples Which of the following statements best explains the pattern seen on the gel with regard to the size and charge of molecules A and B?

C. Molecules AA and BB are negatively charged, and molecule AA is smaller than molecule BB.

Figure 1. Mite Habitat Preferences (by R. colwelli and R. richardsoni) Which of the following is an accurate interpretation of the data in Figure 1 ?

C. R. richardsoni is found significantly more frequently on Species 3 and Species 4 compared to Species 1 and Species 2.

Which of the following is common feature of the illustrated reactions showing the linking of monomers to form macromolecules?

C. Monomers are joined by a covalent bond, and a water molecule is produced.

Which of the following describes a key difference among the 20 amino acids that are used to make proteins?

C. Some amino acids are hydrophobic.

Sucrose is made from joining a glucose molecule and a fructose molecule in a dehydration reaction. What is the molecular formula for this disaccharide?

C12H22O11

The molecular formula for glucose is C6H12O6. What would be the molecular formula for a molecule made by linking three glucose molecules together by dehydration reactions?

C18H32O16

If three molecules of a fatty acid (each with a formula C16H22O2) are joined to a molecule of glycerol (C3H8O3), then the resulting molecule would have the formula

C51H68O6

Three molecules of the fatty acid in question 9 (C16H32O2) are joined to a molecule of glycerol (C3H8O3). The resulting molecule has the formula

C51H98O6

The molecular formula for glucose is C6H12O6. What would be the molecular formula for a polymer made by linking ten glucose molecules together by dehydration reactions?

C60H102O51

Which of the following statements describes the results of this reaction? C6H12O6 + 6 O2 ® 6 CO2 + 6 H2O + Energy

C6H12O6 is oxidized and O2 is reduced.

Based on the data which cell is likely to be most effective In the exchange of materials?

CELL 2.

If the nucleotide sequence of one strand of a DNA helix is 5'GCCTAA3', what would be the 3'-5' sequence on the complementary strand?

CGGATT

Figure 1. Models of a prokaryote, first eukaryotic common ancestor, and last eukaryotic common ancestor. Based on the information provided in the figure, which of the following best describes how membrane-bound organelles provided unique evolutionary advantages to the last eukaryotic common ancestor?

Cells with mitochondria were able to utilize metabolic energy more efficiently.

A structural carbohydrate found in plants

Cellulose

42) Suppose a young boy is always tired and fatigued, suffering from a metabolic disease. Which of the following organelles is most likely involved in this disease? A) lysosomes B) Golgi apparatus C) ribosomes D) mitochondria

Tanya is trying to remember a phone number, so she repeats it until she remembers it. Which of the following best explains why Tanya has chosen this way to remember? (A) Jean Piaget's theory of cognitive development, because she is using her frontal cortex. (B) Jean Piaget's theory of cognitive development, because this theory addresses encoding and storing information. (C) The information processing theory, because she is using deep processing. (D) The information processing theory, because this theory addresses encoding and storing information. (E) The information processing theory, because she is using a mnemonic device.

. Relationships of selected organisms based on catalase structure Which of the following student claims is best supported by the data provided?

Cattle and sheep are separated by only one node, and they are separated from the other organisms by more than one node.

Related to Question 1 Information: Which of the following best describes the change in coyote behavior in the presence of wolves?

C = Decrease, No Effect, No effect, Increase, Increase: According to Figure 2, in the presence of wolves (white bars), the proportion of time spent on rest is less, the proportion of time spent feeding on carcasses is more, and the proportion of time spent on vigilance is more than in the absence of wolves (gray bars). Although the mean proportion of time spent on travel increases in the presence of wolves, the error bars overlap, showing that the difference is not statistically significant.

Figure 1 shows the population fluctuations of phytoplankton and zooplankton in the eastern Pacific Ocean over the course of six years. The major dip in phytoplankton was attributed to a lack of nutrients for phytoplankton. Of the following, which explains why the zooplankton also dipped during the same year and then seemed to cycle over the next three years?

D = The reduction in the phytoplankton population meant that the zooplankton's energy source was drastically reduced, leading to the decrease in the zooplankton population size. After the dip, the phytoplankton provided a steady energy source, and the zooplankton population fluctuated around its carrying capacity: The energy source of zooplankton is the carbon compounds fixed by phytoplankton. Without the proper inorganic nutrients, the phytoplankton population is limited in its photosynthetic activity, leading to an energy deficit in the zooplankton populations. It is also correct that the annual fluctuations in zooplankton represent a stable population cycling around its carrying capacity.

Chiasmata are what we see under a microscope that let us know which of the following is occurring?

D) Crossing over

Which of the following types of evidence will best support the researcher's claim, based on Figure 3-5? A) Evidence that some of the earliest eukaryotes used oxygen to produce ATP by cellular respiration B) Evidence that the earliest plants produced oxygen as a by-product of photosynthesis C) Evidence that some of the earliest organisms carried out photosynthesis without producing oxygen D) Evidence that the Cyanobacteria produced oxygen as a by-product of photosynthesis

D) Evidence that the Cyanobacteria produced oxygen as a by-product of photosynthesis

Measurements of the amount of DNA per nucleus were taken on a large number of cells from a growing fungus. The measured DNA levels ranged from 3 to 6 picograms per nucleus. In which stage of the cell cycle was the nucleus with 6 picograms of DNA?

D) G2

As shown in Figure 1-6, an amino acid must have which of the following properties in order to be incorporated into a polypeptide? A) The ability to remain stable in the presence of water molecules B) An R-Group that is compatible with the R-group of the last amino acid incorporated C) A central carbon atom that reacts with a nitrogen atom to form the peptide bond. D) The ability to form a covalent bond with both its NH2 group and its COOH group

D) The ability to form a covalent bond with both its NH2 group and its COOH group

Cells move to new positions as an embryo establishes its three germ tissue layers during

E) gastrulation.

A bacterium engulfed by a white blood cell through phagocytosis will be digested by enzymes contained in

lysosomes

Initiation of translation

mRNA becomes attached to ribosome, first codon is AUG

homeostasis

maintenance of a steady state, such as a constant temperature, by means of physiological or behavioral feedback responses

Radioactive isotopes can be used in studies of metabolic pathways because

their location or quantity can be experimentally determined because of their radioactivity.

The difference between living and nonliving matter depends not only on the kinds of atoms and molecules present, it also depends on ____.

their organization and interactions

3 Domains and why its better

Bacteria- currently known pros Archaea- diverse group of prokaryotes Eukaryotes- all orgs with cells, true nuclues, single cell, fungi, plants and animals Better--- highlights fact that history of earth has been mostly single celled orgs 2 pro domains---single celled orgs, only some are multicell

If there are 20 chromatids in a cell at metaphase, how many chromosomes are there in each daughter cell following cytokinesis?

Which of the following best describes the role of mitosis in the cell cycle? A Distributing replicated chromosomes to daughter nuclei B Dividing the cytoplasm to form four gametes C Producing organelles and replicating chromosomes D Exchanging genetic material between homologous chromosomes

A Distributing replicated chromosomes to daughter nuclei

Independent assortment of chromosomes is a result of

A) the random and independent way in which each pair of homologous chromosomes lines up at the metaphase plate during meiosis I.

What tissue makes up most of the wood of a tree?

A) xylem

Which of the following factors would tend to increase membrane fluidity?

A greater proportion of unsaturated phospholipid

A mature plant cell that can be distinguished from other eukaryotic cells because it has what

A large central vacuole

Codons

A sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule

In comparison of birds and mammals, having four appendages is...

A shared ancestral character

What cell would most likely have the greatest concentration of densely packed nutrients

A smooth muscle cell in the diaphragm

how water is pulled up through the xylem to the leaves of the plant?

As water exits the leaf, hydrogen bonding pulls more water molecules up through the leaf and xylem by cohesion.

A researcher claims that increased atmospheric carbon dioxide levels cause increased growth rates in plants. Which of the following statements best supports the researcher's claim?

Atmospheric carbon dioxide is the raw material for photosynthesis, which plants rely on for producing sugars and other organic compounds.

For the following questions: Graphs I-IV depict the effect of pH on the activity of four different hydrolytic enzymes. Enzymes with their highest activity at an alkaline (basic) pH are represented by which of the following graphs? A I only B II only C III only D I and III only E I and IV only

B II only

Which of the following best predicts why the recombinant bacteria will fail to produce the eukaryotic protein?

Bacteria and eukaryotes use different mRNA codons for the same amino acids during translation.

Of what type of human trait transmission is blood type an example? A. Dominant alleles B. Codominant alleles C. Recessive alleles D. Y-linked alleles

Codominant alleles

Because of the unique properties of water associated with hydrogen bonding, water evaporates from pores on the leaves of plants and draws up water molecules in a continuous chain from the roots up through the vascular tissue of plants. Which of these groups of terms describes the process and properties of water that explain this?

Cohesion, adhesion, and transpiration

Some researchers claim that the decrease in plant species richness of this woodlot is unrelated to human activities over the last forty years. Which of the following would be an appropriate alternative hypothesis?

During the last few decades, tall buildings have been built around the woodlot, and species 3, 4, and 5 are shade‑intolerant plants

A researcher claims that the initial rise of oxygen in earths early atmosphere resulted from the metabolic activity of prokaryotic organisms. Which of the following types of evidence will best support the researchers claim?

Evidence that the Cyanobacteria produce oxygen as a byproduct of photosynthesis.

Which number represents DNA synthesis?

MPF reaches its threshold concentration at the end of this stage.

III

chromosomes replicate

Interphase

Anticodon

One end of tRNA molecule that bears a nucleotide triplet

Using a significance level of p=0.05, which of the following statements best completes a chi-square goodness-of-fit test for a model of independent assortment?

The calculated chi-square value is 3.91, and the critical value is 7.82. The null hypothesis cannot be rejected.

Which hypothesis is most likely to be produced for their initial investigation?

The three-dimensional amino acid structure of the enzyme may have been altered

when a species invades a new habitat and evolves rapidly into several new species to better exploit new resources what has occurred?

adaptive radiation

mutations

all of these

Negative Feedback-

body temp

regeneration

development of a complete individual from a piece of an organism

One of the primary functions of RNA molecules is to

function in the synthesis of proteins.

melatonin

regulates daily rhythms and is produced by the pineal gland

Which of the following is present in a prokaryotic cell?

ribosome

Which structure is the site of the synthesis of proteins that may be exported from the cell?

rough ER

A fatty acid that has the formula C16H32O2 is

saturated

budding

new individuals form as outgrowths, or buds, from me bodies of mature animals

Eukaryotes transcribe RNA from DNA that contains introns and exons. Alternative splicing is one posttranscriptional modification that can create distinct mature mRNA molecules that lead to the production of different proteins from the same gene. Figure 1 shows a gene and the RNA produced after transcription and after alternative splicing. Figure 1. Model of posttranscriptional alternate splicing of mRNA A cell needs to metabolize the substrate illustrated in Figure 1 for a vital cellular function. Which of the following best explains the long-term effect on the cell of splicing that yields only enzyme C mRNA?

(A) The cell will die because it is unable to metabolize the substrate without enzyme AA, which is structurally specific for the substrate shown.

Huntington's disease, an autosomal dominant disorder, is caused by a mutation in the HTT gene. The HTT gene contains multiple repeats of the nucleotide sequence CAG. A person with fewer than 35 CAG repeats in the HTT gene is unlikely to show the neurological symptoms of Huntington's disease. A person with 40 or more CAG repeats almost always becomes symptomatic. Due to errors in meiosis, an individual without symptoms of Huntington's disease can produce gametes with a larger number of CAG repeats than there are in their somatic cells. A woman develops Huntington's disease. Her father had the disorder. Her mother did not, and there is no history of the disorder in the mother's family. Which of the following best explains how the woman inherited Huntington's disease?

(B) She inherited an allele with more than 40 CAG repeats in the HTT gene from her father.

Figure 1 represents a portion of a process that occurs during protein synthesis. Figure 1. Model of selected features of DNA transcription Which claim is most consistent with the information provided by the diagram and current scientific understanding of gene regulation and expression?

(B) Some sequences of DNA can interact with regulatory proteins that control transcription.

(melanin synthesis pt 1) In mammals, the dark color of skin, hair, and eyes is due to a pigment called melanin. Melanin is produced by specialized skin cells called melanocytes. The melanin is then transferred to other skin cells called keratinocytes. Melanocytes synthesize melanin in a multistep metabolic pathway (Figure 1). The amount of melanin produced is dependent on the amount of the enzymes TYR, TRP2, and TRP1 present inside melanocytes. Figure 1. Melanin synthesis pathway The peptide hormone α-melanocyte stimulating hormone (α-MSH) activates a signal transduction pathway leading to the activation of MITF. MITF is a transcription factor that increases the expression of the TYR, TRP2, and TRP1 genes (Figure 2). Figure 2. Activation of melanin synthesis genes in melanocytes Some mammals increase melanin production in response to ultraviolet (UV) radiation. The UV radiation causes damage to DNA in keratinocytes, which activates the p53 protein. p53 increases the expression of the POMC gene. The POMC protein is then cleaved to produce α-MSH. The keratinocytes secrete α-MSH, which signals nearby melanocytes. The increased melanin absorbs UV radiation, reducing further DNA damage Figure 3. Production of α-MSH in keratinocytes in response to UV radiation Which of the following claims about the TYR, TRP2, and TRP1 mammalian genes is most likely to be accurate?

(B) the TYR, TRP2, and TRP1 genes may be located on different chromosomes but are activated by the same transcription factor.

Lynch syndrome is an inherited condition associated with an increased risk for colon cancer, as well as certain other cancers. Mutations in one of several genes involved in DNA repair during DNA replication have been associated with Lynch syndrome. DNA sequencing was performed for an individual. The results indicated that the individual carries one of the dominant alleles that has been associated with Lynch syndrome. Which of the following best explains how the results should be interpreted?

(B) the individual has an increased risk of developing colon cancer.

Cystic fibrosis (CF) is a progressive genetic disease that causes persistent lung infections and affects the ability to breathe. CF is inherited in an autosomal recessive manner, caused by the presence of mutations in both copies of the gene for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Partial nucleotide sequences and the corresponding amino acid sequences for an unaffected individual and an affected individual are modeled in Figure 1. Figure 1. CFTR protein sequences in unaffected and affected individuals Based on the information in Figure 1, which type of mutation explains the nature of the change in DNA that resulted in cystic fibrosis in the affected individual?

Scientists conducted a transformation experiment using E. coli bacteria and the pTru plasmid. Samples of the pTru plasmid (lane A) and the chromosomal DNA from two different E. coli strains that the scientists attempted to transform (lane B and lane C) were compared using gel electrophoresis. The results are shown in Figure 1. Figure 1. Results of E. coli transformation with pTru plasmid Which of the following statements best explains the experimental results observed in Figure 1 ?

Figure 1 depicts a simplified model of a replication bubble. Figure 1. DNA replication bubble. Which of the following best explains how this model illustrates DNA replication of both strands as a replication fork moves?

(C) I is synthesized continuously in the 5′ to 3′ direction, and III is synthesized in segments in the 5' to 3′ direction

All cells must transcribe rRNA in order to construct a functioning ribosome. Scientists have isolated and identified rRNA genes that contribute to ribosomal structure for both prokaryotes and eukaryotes. Figure 1 compares the transcription and processing of prokaryotic and eukaryotic rRNA. Figure 1. Comparison of rRNA processing in prokaryotes and eukaryotes Which of the following statements provides the best explanation of the processes illustrated in Figure 1 ?

(C) Sections of the pre-rRNA are removed, and the mature rRNA molecules are available to combine with proteins to form the ribosomal subunits.

An evolutionary biologist hypothesizes that two morphologically similar plant species are not closely related. To test the hypothesis, the biologist collects DNA samples from each of the two plant species and then uses restriction enzymes to cut the DNA samples into fragments, which are then subjected to gel electrophoresis. The results are shown in Figure 1. Figure 1. DNA analysis of two species Given the results shown in Figure 1, which of the following correctly describes a relationship between the two species?

Which of the following best explains how the pattern of DNA arrangement in chromosomes could be used, in most cases, to determine if an organism was a prokaryote or a eukaryote?

(D) Prokaryotic DNA: singular circular chromosome Eukaryotic DNA: multiple linear chromosomes

Cycloheximide (CHX) is a eukaryote protein synthesis inhibitor. It is used in biomedical research to inhibit protein synthesis in eukaryotic cells studied in vitro. Its effects are rapidly reversed by simply removing it from the culture medium. In a translation experiment using a fungus culture, radiolabeled amino acids were added to the culture, allowing the researchers to measure the growth of a single polypeptide chain by measuring counts per minute (CPM). As the chain grew, the CPM increased. After a certain amount of time, CHX was added to the mixture, and the experiment continued. After an additional amount of time, the CHX was removed from the culture medium. Which of the following graphs best predicts the data collected during the experiment?

(D) (graph CPM x Time) increase=> Inhibitor added=> constant=> inhibitor removed=> decrease

(melanin synthesis pt 5) Which of the following best explains a process occurring between point 1 and point 2 in Figure 3 ?

(D) A poly‑A tail is added to RNA.

Labeled nucleotides were supplied to a cell culture before the cells began DNA replication. A simplified representation of the process for a short segment of DNA is shown in Figure 1. Labeled DNA bases are indicated with an asterisk (*). Figure 1. A simplified representation of the DNA replication process Which of the following best helps explain how the process represented in Figure 1 produces DNA molecules that are hybrids of the original and the newly synthesized strands?

(D) Each newly synthesized strand remains associated with its template strand to form two copies of the original DNA molecule.

A simplified model of a DNA replication fork is represented in Figure 1. The protein labeled Enzyme 1 carries out a specific role in the DNA replication process. Figure 1. A simplified model of a DNA replication fork Which of the following statements best explains the role of Enzyme 1 in the DNA replication process?

(D) Enzyme 1 is a topoisomerase that relieves tension in the overwound DNA in front of a replication fork.

(melanin synthesis pt 4) Based on the information provided in Figure 1 and Figure 2, which of the following best predicts the effects of a mutation in the promoter of the TYR gene that prevents it from being transcribed?

(D) Skin pigmentation will not be able to change, resulting in a negative selection pressure.

Exposure to ultraviolet (UV) radiation is the leading cause of skin cancer in humans. Figure 1 shows a model of how UV exposure damages DNA. Figure 1. Model of damage to DNA caused by UV exposure Which of the following statements best explains what is shown in Figure 1 ?

(D) UV photons cause dimers to form, leading to misshapen DNA, which results in replication and transcription errors.

Small single-stranded RNA molecules called microRNAs (miRNAs) are capable of base pairing with specific binding sites in the 3′ untranslated region of many mRNA transcripts. Transcription of gene Q yields an mRNA transcript that contains such an miRNA binding site, which can associate with miRNA‑delta, a specific miRNA molecule. Which of the following best supports the claim that binding of miRNA‑delta to the miRNA binding site inhibits translation of gene Q mRNA?

(D) When the miRNA binding site sequence is altered, translation of Q mRNA occurs in the presence of miRNA-delta.

The trp operon in E. coli is an example of a repressible operon that consists of genes coding for enzymes used to synthesize tryptophan. When tryptophan levels are high, the operon is turned off and these genes are not transcribed. However, it is also known that tryptophan does not bind directly to the operator DNA sequence. A regulatory gene called trpR has also been discovered although it is not part of the trp operon. The proposed model of how tryptophan acts as a corepressor is shown in Figure 1. Figure 1. Model of proposed regulation of the trp operon by corepressors trp repressor and tryptophan Which of the following evidence best supports a claim that tryptophan functions as a corepressor?

(D) When trpR is mutated, the trp operon is transcribed regardless of tryptophan levels.

levels of taxa

(from less specific to more specific) domains => kingdom => phylum => class => order => family => genus => species

In the Arizona populations, the melanocortin-1 receptor (MC1R) gene is responsible for coat color phenotype (light or dark). The MC1RD allele, which results in a dark coat, is dominant to the d allele. Researchers collected samples of mice from all six study sites and sequenced the MC1R gene. They also collected mice with dark coats from a location in New Mexico, the Carrizozo lava flow, to determine if the MC1Rgene was also responsible for the dark coat colors observed in that population. The rock pocket mouse population in Carrizozo is isolated from the populations in Arizona. Table 1 presents the genotypic data from sampled mice from all seven locations. Which of the following is closest to the frequency of the MC1RD allele in the Tule Mountain population?

0.03

Testosterone is a small steroid hormone that is important in cell signaling. Which of the following indicates where testosterone enters a cell and why it is able to cross at that point?

1, because testosterone is nonpolar and can diffuse through the membrane.

Which of the following indicates where testosterone enters the cell and why is able to cross at that point?

1, because testosterone is nonpolar and can diffuse through the membrane.

The 3 main points from Phylogenetic tree-

1. show pattern of descent, not phenotypic similarity 2. sequence of branching does not indicate age 3. don't assume that a taxon on a phylogenetic tree evolved from taxon next to it.

cola-2; orange juice-3; beer-4; coffee-5; human blood-7.4 What is the concentration of hydroxide ions in 1 liter of beer?

1.0 x 10^-10

Taking into account the bonding capacities or valences of carbon (C) and oxygen (O), how many hydrogen (H) must be added to complete the following structural diagram of the molecule? O= C-C-C=C-C-C O-

A globular blood protein that transports vitamin A is 127 amino acids long. How many water molecules were produced in the synthsis pf the protein, and by what chemical process were the amino acids joined together?

126, dehydration

Chlorine has an atomic number of 17 and a mass number of 35. How many electrons would a chloride ion have?

Which of the following atomic numbers would describe the element that is least reactive?

Which of the following substances would you add to enough water to yield 1 liter of solution in order to make a 0.1M solution of glucose (C6H12O6)? The mass numbers for these elements are approximately C=12, O=16, and H=1.

18g of glucose

Testosterone movement across the cellular membrane Testosterone is a small steroid hormone that is important in cell signaling. Which of the following indicates where testosterone enters a cell and why it is able to cross at that point?

2, because testosterone covalently binds to a surface protein and transports into the cell.

What fraction of the carbon dioxide exhaled by animals is generated by the reactions of the citric acid cycle, if glucose is the sole energy source?

2/3

How many different kinds of polypeptides, each composed of 12 amino acids, could be synthesized using the 20 common amino acids?

2012

Based on table 1, what percent of the life cycle of yeast cells is spent in DNA replication?

25 percent

Based on Table 5-5, the mean map distance between gene R and gene L is closest to which of the following? A) 0.28 map units B) 28 map units C) 0.14 map units D) 14 map units

28 map units

The mean map distance between gene R and gene L is closest to which of the following?

28 map units

The mean number of fruit flies per student that are homozygous recessive for both genes is closest to which of the following?

12/6 C, 16/8 O, 1/1 H, 14/7 N, 32/16 S, 31/15 P What is the atomic mass of phosphorus?

end result of spermatogenesis

4 spermatids

If a DNA sample were composed of 10% thymine, what would be the percentage of guanine?

12/6 C, 16/8 O, 1/1 H, 14/7 N, 32/16 S, 31/15 P How many electrons does phosphorus have in its valence shell?

Which of the following pairs of base sequences could form a short stretch of a normal double helix of DNA?

5' -ATGC-3' with 5' -GCAT-3'

If one strand of a DNA molecule has the sequence of bases 5'ATTGCA3', the other complementary strand would have the sequence

5'TGCAAT3'.

Sex chromosomes determine the phenotype of sex in humans. Embryos containing XX chromosomes develop into females, and embryos containing XY chromosomes develop into males. The sex chromosomes separate during meiosis, going to different gamete cells. A woman is heterozygous for the X-linked recessive trait of hemophilia A. Her sex chromosomes can be designated as XHXh. During meiosis the chromosomes separate as shown in Figure 1. Figure 1. Transmission pattern for sex chromosomes of a woman heterozygous for hemophilia A into gametes If the woman and a man with normal clotting function have children, what is the probability of their children exhibiting hemophilia A?

50 percent for sons, 0 percent for daughters

(1 liter of solution in order to make a 0.1M solution of glucose (C6H12O6)? The mass numbers for these elements are approximately C=12, O=16, and H=1.) How many molecules of glucose would be in 1 liter of the 0.1M solution made?

6x10^22

Researchers performed a dihybrid cross with coffee bean plants to investigate whether the inheritance of two traits (height and stem circumference) follows Mendel's law of independent assortment. The data for the F2 generation are presented in Table 1. Which of the following is closest to the calculated chi-square (χ2) value for the data presented in Table 1?

72.01

How many amino acids differ bewteen the monkey and the human sequences?

What coefficients must be placed in the blanks to balance the following chemical reaction? C5H12+___O2->___CO2+___H2O

8;5;6

If nine molecules of a monosaccharide with the formula C6H12O6 are assembled to produce a complex carbohydrate, how many atoms of hydrogen will be in the final polymer?

What preentage of monkey B-globin amino acids is identical to human sequence? (This is call the percentage idently between the monkey and human B-globin sequences.)

94.5%

Using the same procedure, notice that humans and gibbons differ in amino acids at two locations. What percentage of gibbon B-globin amino acids is identical to the human sequence? (this is called the percentage identity bewteen the gibbin and human B-globin sequences)

98.6%

1) The smallest cell structure that would most likely be visible with a standard (not superresolution) researchgrade light microscope is a _____. A) mitochondrion B) microtubule C) ribosome D) microfilament

16) What is the function of the nuclear pore complex found in eukaryotes? A) It regulates the movement of proteins and RNAs into and out of the nucleus. B) It synthesizes the proteins required to copy DNA and make mRNA. C) It selectively transports molecules out of the nucleus, but prevents all inbound molecules from entering the nucleus. D) It assembles ribosomes from raw materials that are synthesized in the nucleus.

17. A plant with straight spikes is crossed with a plant with curly spikes. Their offspring have both straight and curly spikes. What is this an example of? a. Codominance b. Incomplete Dominance c. Corecessive d. Incomplete Recessive e. None of the above

19. The fact that only one of two genes from each parent is distributed to each gamete (randomly) is known as what? a. Law of Segregation b. Law of Independent Assortment c. Crossing over d. Polar bodies e. Zygote

22. A homozygous type A mother crosses with a type O father. What is the likelihood that their offspring will be type O? a. 0% b. 25% c. 50% d. 75% e. 100%

27) Which structure is the site of the synthesis of proteins that may be exported from the cell? A) rough ER B) plasmodesmata C) Golgi vesicles D) free cytoplasmic ribosomes

3. What stage of meiosis does crossing over occur? a. Prophase I b. Metaphase I c. Anaphase I d. Telophase I e. Cytokinesis I

38) The evolution of eukaryotic cells most likely involved _____. A) endosymbiosis of an aerobic bacterium in a larger host cell—the endosymbiont evolved into mitochondria B) anaerobic archaea taking up residence inside a larger bacterial host cell to escape toxic oxygen—the anaerobic bacterium evolved into chloroplasts C) an endosymbiotic fungal cell evolving into the nucleus D) acquisition of an endomembrane system and subsequent evolution of mitochondria from a portion of the Golgi

41) Cyanide binds with at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the _____. A) mitochondria B) peroxisomes C) lysosomes D) endoplasmic reticulum

46) Amoebae move by crawling over a surface (cell crawling), which involves _____. A) growth of actin filaments to form bulges in the plasma membrane B) setting up microtubule extensions that vesicles can follow in the movement of cytoplasm C) reinforcing the pseudopod with intermediate filaments D) cytoplasmic streaming

5) What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division? A) standard light microscopy B) scanning electron microscopy C) transmission electron microscopy

51) Cells require which of the following to form cilia or flagella? A) tubulin B) laminin C) actin D) intermediate filaments

58) In plant cells, the middle lamella _____. A) allows adjacent cells to adhere to one another B) prevents dehydration of adjacent cells C) maintains the plant's circulatory system D) allows for gas and nutrient exchange among adjacent cells

59) Where would you expect to find tight junctions? A) in the epithelium of an animal's stomach B) between the smooth endoplasmic reticulum and the rough endoplasmic reticulum C) between plant cells in a woody plant D) in the plasma membrane of prokaryotes

6. Gregor Mendel concluded what about dominant and recessive phenotypes? a. They come in 3:1 ratios b. They come in 1:1 ratios c. They come in 9:3:3:1 ratios d. They come in 3:3:1:1 ratios e. None of the above

Which of the following describes sexual orientation? (A) Developing an inherent attraction or romantic relationship with a given gender or genders (B) Feeling gender is consistent throughout the life span (C) Identifying as a specific gender (D) Developing an overgeneralization about a group of individuals based on their gender (E) Learning a set of expectations that one feels are appropriate for various genders

Which of the following scenarios best illustrates Jean Piaget's theory of cognitive development? (A) Jimmy, an infant, is learning about the world by exploring with his hands and his mouth. (B) Milen, a sixth grader, is learning a new math concept with the help of a more advanced math student. (C) Frances, a toddler, is struggling between feelings of autonomy and self-doubt. (D) Riaesha, a seventh grader, is learning because her teacher models an activity and then steps back, providing assistance as needed. (E) Matthew, a three year old, tells his mother he wants to marry her when he grows up.

Which scenario best illustrates what Erik Erikson would predict would happen in middle adulthood? (A) Timothy has worked at a bank for many years, where he feels rather stifled. He then decides to volunteer to read books to young children because he finds this volunteerism fulfilling. (B) Shanika works hard to accomplish new things and is very proud when she does. (C) Jorge likes to reminisce about his life. He thinks of the things he is proud of and the times he was disappointed in his experiences. (D) Anthony likes when he does things independently and feels bad when he cannot accomplish things on his own. (E) Amelia has tried many different ways of defining herself over the past few years.

The following questions refer to an experiment that is set up to determine the relative volume of O2 consumed by germinating and nongerminating (dry) pea seeds at two different temperatures. The change in volume is detected by using a respirometer over a given period of time. The data are given below. The rate of oxygen consumption in germinating pea seeds at 26ºC is A 0.05 mL / min B 0.25 mL / min C 0.50 mL / min D 0.75 mL / min E 1.00 mL / min

A 0.05 mL / min

An experiment to measure the rate of respiration in crickets and mice at 10o C and 25o C was performed using a respirometer, an apparatus that measures changes in gas volume. Respiration was measured in mL of O2 consumed per gram of organism over several five-minute trials, and the following data were obtained. During aerobic cellular respiration, oxygen gas is consumed at the same rate as carbon dioxide gas is produced. In order to provide accurate volumetric measurements of oxygen gas consumption, the experimental setup should include which of the following? A A substance that removes carbon dioxide gas B A plant to produce oxygen C A glucose reserve D A valve to release excess water

A A substance that removes carbon dioxide gas

An experiment to measure the rate of respiration in crickets and mice at 10oC and 25oC was performed using a respirometer, an apparatus that measures changes in gas volume. Respiration was measured in mL of O2 consumed per gram of organism over several five-minute trials and the following data were obtained. During aerobic cellular respiration, oxygen gas is consumed at the same rate as carbon dioxide gas is produced. In order to provide accurate volumetric measurements of oxygen gas consumption, the experimental setup should include which of the following? A A substance that removes carbon dioxide gas B A plant to produce oxygen C A glucose reserve D A valve to release excess water

A A substance that removes carbon dioxide gas

Antidiuretic hormone (ADH) is important in maintaining homeostasis in mammals. ADH is released from the hypothalamus in response to high tissue osmolarity. In response to ADH, the collecting duct and distal tubule in the kidney become more permeable to water, which increases water reabsorption into the capillaries. The amount of hormone released is controlled by a negative feedback loop. Based on the model presented, which of the following statements expresses the proper relationship between osmolarity, ADH release, and urine production? A As tissue osmolarity rises, more ADH is released, causing less water to be excreted as urine. B As tissue osmolarity rises, less ADH is released, causing less water to be excreted as urine. C As tissue osmolarity rises, more ADH is released, causing more water to be excreted as urine. D As tissue osmolarity rises, less ADH is released, causing more water to be excreted as urine.

A As tissue osmolarity rises, more ADH is released, causing less water to be excreted as urine.

The figures below illustrate the similarities between ATP synthesis in mitochondria and chloroplasts. The figures can best assist in answering which of the following questions? A Do electron transport chains create a gradient so that ATP synthase can generate ATP molecules? B What are the sources of energy that drive mitochondrial and chloroplast electron transport systems? C What is the optimal temperature at which ATP synthase chemically converts ADP and a phosphate group into one molecule of ATP? D What is the evolutionary relationship between the ATP synthase in mitochondria and the ATP synthase in chloroplasts?

A Do electron transport chains create a gradient so that ATP synthase can generate ATP molecules?

The diagram below shows energy changes in a specific chemical reaction with and without the addition of an enzyme to the reaction. Which of the following questions can best be answered by the diagram? A Does the addition of an enzyme reduce the activation energy required for a reaction? B Does the addition of an enzyme result in the formation of covalent bonds? C Does the addition of an enzyme produce a greater amount of products? D Does the addition of an enzyme change the pathway for the reaction?

A Does the addition of an enzyme reduce the activation energy required for a reaction?

Epinephrine is a protein hormone found in many animals. Epinephrine stimulates a signaling pathway that results in the breakdown of glycogen to glucose in the liver cells. Which of the following describes the initial steps in the process whereby epinephrine stimulates glycogen breakdown? A Epinephrine binds to a cell-surface receptor; the activated receptor stimulates production of the second messenger, cAMP. B Epinephrine binds to a cell-surface receptor; the activated receptor catalyzes the conversion of glycogen to glucose. C Epinephrine diffuses through the plasma membrane; the hormone dimerizes in the cytosol. D Epinephrine is taken into the cell by endocytosis; glycogen is converted to glucose in the endocytotic vesicle.

A Epinephrine binds to a cell-surface receptor; the activated receptor stimulates production of the second messenger, cAMP.

Figure 1. Reaction catalyzed by phosphofructokinase (PFK) during glycolysis Phosphofructokinase (PFK) is an enzyme that catalyzes the conversion of fructose 6-phosphate to fructose 1,6-bisphosphate during glycolysis, as represented in Figure 1. PFK can be allosterically inhibited by ATP at high concentrations. Which of the following is the benefit of regulating glycolysis by the concentration of ATP? A Glycolysis proceeds when the intracellular concentration of ATP is low, which provides ATP to drive cellular reactions. B Glycolysis proceeds when the intracellular concentration of ATP is high and the cell stores ATP for future use. C Glycolysis is inhibited when the intracellular concentration of ATP is low because PFK requires ATP as a substrate for the reaction it catalyzes. D Glycolysis is inhibited when the intracellular concentration of ATP is high because ATP will compete with fructose 1,6-bisphosphate for binding to the active site on the enzyme.

A Glycolysis proceeds when the intracellular concentration of ATP is low, which provides ATP to drive cellular reactions.

A respirometer is a container used to measure the amount of oxygen consumed by an organism. A respirometer was used to determine how environmental temperature affects the uptake of oxygen in one 300-gram rat and one 50-gram mouse. The results of this experiment are shown on the graph below. Which of the following would most adversely affect the validity of this experiment? A Large variation in metabolic rates between individuals of a species B Repeating the experiment several times C Using a brown rat and a white mouse D Using a thermometer that consistently read 2°C too low E Using a scale that consistently indicated 2 grams too much

A Large variation in metabolic rates between individuals of a species

A respirometer is a container used to measure the amount of oxygen consumed by an organism. A respirometer was used to determine how environmental temperature affects the uptake of oxygen in one 300-gram rat and one 50-gram mouse. The results of this experiment are shown on the graph below. Which of the following hypotheses is best supported by the results of this experiment? A Metabolic rate per gram of tissue is higher in smaller mammals. B Metabolic rate per gram of tissue is not related to body mass. C Mice produce less CO2 per gram of tissue than do rats. D Rats consume more food per gram of tissue than do mice. E Rats lose more heat per gram of tissue than do mice.

A Metabolic rate per gram of tissue is higher in smaller mammals.

For following group of questions first study the description of the data and then choose the one best answer to each question following it and fill in the corresponding oval on the answer sheet. To study the actions of the enzyme catalase on hydrogen peroxide, students performed the following experiment. Catalase was extracted from potatoes by blending raw potatoes in a blender with cold distilled water. The filtrate was stored on ice. The following hydrogen peroxide solutions were made: 1 percent, 5 percent, 10 percent, and 15 percent. Filter paper disks were soaked in the catalase filtrate and dropped into beakers containing the various solutions. The activity of the enzyme was measured by the amount of time it took for the disks to float to the surface of the solution on the bubbles produced by the reaction. The following data were obtained. Which of the following experimental designs should the students use as a control for the experiment? A Place a catalase-soaked disk in a beaker of water. B Drop the disks from different heights into the solution. C Poke the floating disks back down to the bottom of the beaker and retime the rise of the disks. D Shake the beakers during the time the disks are rising. E Dip the disks in the 5% solution before putting them in any other solution.

A Place a catalase-soaked disk in a beaker of water.

An experiment to measure the rate of respiration in crickets and mice at 10o C and 25o C was performed using a respirometer, an apparatus that measures changes in gas volume. Respiration was measured in mL of O2 consumed per gram of organism over several five-minute trials, and the following data were obtained. According to the data, the mice at 10o C demonstrated greater oxygen consumption per gram of tissue than did the mice at 25o C. This is most likely explained by which of the following statements? A The mice at 10o C had a higher rate of ATP production than the mice at 25o C. B The mice at 10o C had a lower metabolic rate than the mice at 25o C. C The mice at 25o C weighed less than the mice at 10o C. D The mice at 25o C were more active than the mice at 10o C.

A The mice at 10o C had a higher rate of ATP production than the mice at 25o C.

What is the difference between a molecule and a compound?

A compound consists of two or more elements in a fixed ratio; a molecule has two or more covalently bonded atoms of the same or different elements.

Insulin, a hormone secreted by pancreatic cells, stimulates glucose uptake in skeletal muscle cells by mobilizing glucose transporter proteins (GLUT4) to the plasma membrane. As depicted in Figure 1, binding of insulin to the insulin receptor triggers an intracellular signaling cascade in which certain molecules activate other molecules in a relay of the hormone signal to cell targets. One outcome of the signaling cascade is mobilization of GLUT4 from vesicle storage sites in the cytoplasm to sites at the cell surface, where GLUT4 allows glucose to enter the cell. In type 2 diabetes, the cellular response to insulin is disrupted, and individuals with type 2 diabetes cannot properly regulate their blood glucose levels. In an investigation of the insulin signaling pathway, samples of skeletal muscle were isolated from individuals who have type 2 diabetes and from individuals who do not. The results of several experiments that were performed on the muscle samples are shown in Figure 2, Figure 3, and Figure 4. A The relatively low levels of glucose uptake in individuals with type 2 diabetes indicate that mobilization of GLUT4 to the cell surface is reduced in muscle cells of those individuals. B The relatively low levels of glucose uptake in individuals with type 2 diabetes indicate that no functional GLUT4 protein is produced in the muscle cells of those individuals. C The absence of activated insulin receptors in individuals with type 2 diabetes indicates that no insulin is secreted by the pancreatic cells of those individuals. D The absence of activated IRS-1 in individuals with type 2 diabetes indicates that no functional insulin receptor protein is produced in the muscle cells of those individuals.

A The relatively low levels of glucose uptake in individuals with type 2 diabetes indicate that mobilization of GLUT4 to the cell surface is reduced in muscle cells of those individuals.

In response to elevated blood glucose levels, beta (β) cells in the pancreas release insulin, a regulatory hormone. Insulin signals body cells to take up glucose from the blood, which returns blood glucose levels back to normal. Type 1 diabetes is an autoimmune disorder that destroys β-cells, resulting in elevated blood glucose levels. Researchers have proposed that diabetes could be treated by implanting human embryonic stem cells (hESCs) that have been induced to develop into β-cells (hESC-β). To test the proposed treatment, the researchers set up two groups of genetically identical mice and implanted the mice from one group with hESC-β cells. Several weeks after the hESC-β implant, both groups of mice were given a drug (STZ) that selectively destroys the naturally occurring mouse β-cells but does not affect the implanted hESC-β cells. Figure 1 shows a comparison of average blood glucose levels in both groups of mice. A The treatment would fail because insulin produced by implanted hESC-β cells will not stimulate glucose uptake by body cells. B The treatment would fail because the implanted hESC-β cells would require more glucose than the body can produce. C The treatment would succeed because the implanted hESC-β cells can express the gene that codes for human insulin. D The treatment would succeed because the body cells would secrete more insulin in the presence of the implanted hESC-β cells.

A The treatment would fail because insulin produced by implanted hESC-β cells will not stimulate glucose uptake by body cells.

A student placed 20 tobacco seeds of the same species on moist paper towels in each of two petri dishes. Dish A was wrapped completely in an opaque cover to exclude all light. Dish B was not wrapped. The dishes were placed equidistant from a light source set to a cycle of 14 hours of light and 10 hours of dark. All other conditions were the same for both dishes. The dishes were examined after 7 days and the opaque cover was permanently removed from dish A. Both dishes were returned to the light and examined again at 14 days. The following data were obtained. According to the results of this experiment, germination of tobacco seeds during the first week is A increased by exposure to light B unaffected by light intensity C prevented by paper towels D accelerated in green-leaved seedlings

A increased by exposure to light

Zebra mussels, Dreissena polymorpha, were introduced into the Great Lakes on shipping vessels, first appearing in Lake St. Clair in the 1980s. Since that time, they have rapidly expanded in range, as shown in Figure 1. Figure 1. Map showing the current range of zebra mussels in the United States Which of the following best supports the alternate hypothesis that zebra mussels display characteristics of an invasive species?

A = Lacking natural predators and able to outcompete native species of mussels and other freshwater species for food, zebra mussels have experienced exponential population growth and rapid expansion into new habitats: Because invasive species typically do not have natural predators in the habitats into which they are introduced, they can experience rapid exponential population growth. In addition, because these mussels are able to outcompete native species, zebra mussel range has expanded rapidly.

Figure 1 shows a food web that describes the relationships within a community containing nine species. Each circle represents a separate species. The size of the circle represents the population size of the species relative to other species in the same trophic level. Figure 1. Trophic relationships among organisms in a community Based on the information in Figure 1, which of the following best predicts a short-term effect of removing secondary consumer X from the community?

A = No Consumer X and a significantly larger white striped circle (for the primary consumer), with two much smaller circles under it: If secondary consumer X is removed, then the leftmost primary consumer will increase in number. Consequently, the two producer species that this primary consumer eats will decrease in number. Note that disturbance events that remove a secondary consumer species can cause large shifts in community composition when the trophic web consists of only a few strong links instead of many weak links.

Climate change can affect oceanic ecosystems and their food webs. In the East China Sea (ECS), three major climactic events were considered: the Pacific Decadal Oscillation (PDO), the East Asia winter monsoon (EAWM), and the El Niño Southern Oscillation. Figure 1 shows the relationships among these climactic events, surface sea temperature (SST), amount of phytoplankton, and copepod abundance. Copepods are important primary consumers in this ecosystem, and many species of fish depend on copepods as a food source. Solid arrows on the diagram indicate a statistically significant effect. The thicker the arrow, the greater the effect. Dashed arrows indicate statistically insignificant relationships. Figure 1. Structural equation model deciphering interactions among climate, phytoplankton, and copepods in the southern East China Sea. Solid arrows indicate significant effects, with the thickness of the arrow reflecting the relative effect. Dashed arrows indicate inconsequential effects. What do the data in Figure 1 suggest about a null hypothesis that the East China Sea ecosystem is unaffected by climactic events?

A = The null hypothesis is rejected since there are significant effects of EAWM and PDO on surface sea temperature and copepod abundance: The null hypothesis should be rejected because the data indicate that the EAWM and the PDO have significant effects on surface sea temperature as well as copepod abundance.

Bison in Yellowstone National Park have a food-limited carrying capacity that determines how their population grows. If the population grows too large, some bison will either starve or migrate to search for more food. The park is able to support a maximum population of 4,500 bison. Park conservation officials must watch the population and prevent the bison from overpopulating, since they would migrate to nearby farms, causing agricultural damage and creating hazards to drivers. The bison begin to migrate when the population reaches 4,000 because of competition for food. If the current population size of bison is 3,652 and the maximum growth rate of the population is 0.28, calculate the population size after one year and determine whether the park will need to take measures to control the population.

A = The population will be 3,845 after a year. The bison will not pose a problem until the following year, and no conservation action will need to take place: dN/dt=rmaxN((K−N)/K) should be used to determine the one-year change in population size: 0.28×3,652((4,500−3,652)/4,500)=193. Adding 193 to 3,652 projects a population of 3,845, so the population will not reach the point at which bison migration occurs. However, it will reach a level to initiate migration the following year.

Related to Question 1 Information: Identify the independent variable for the experimental results shown in Figure 2.

A = The presence of wolves: The independent variable is selected by the researchers, and the researchers test its effect on the dependent variable. In this experiment, the researchers were looking at the effect of wolves' presence on the behavior of coyotes. Therefore, the presence of wolves is the independent variable, and the behavior of coyotes is the dependent variable.

Final problem related to Question 1: Following the reintroduction of wolves to Yellowstone National Park, researchers measured the mean height of young aspen trees in upland and streamside areas. Which of the following is the most likely cause of the change in mean aspen height from 1998 to 2010 ?

A = The reintroduction of wolves led to a decrease in the population of elk, allowing aspen trees to grow taller: Top carnivores are keystone species, meaning they have a larger role in maintaining an ecosystem than would be expected by their population size. After wolves were eliminated from Yellowstone National Park, the population of elk rose dramatically. The high elk population led to the overgrazing of plant species, including aspen. With the reintroduction of wolves, the elk population has declined, allowing plant species to recover.

Researchers were studying the effects of microbes on the growth of the yellow bedstraw plant, Galium verum. They grew yellow bedstraw plants under four treatments: in the presence of soil bacteria only, arbuscular mycorrhizal (AM) fungi only, both bacteria and AM fungi, or neither. After 6 months, they measured the biomass of the plants (Figure 1). Figure 1. The Effect of Soil Microbes on the Biomass of Galium verum Which of the following best describes a statistically significant relationship indicated in Figure 1 ?

A = Yellow bedstraw plants grow significantly more in the presence of both soil bacteria and AM fungi (treatment 4) than in the presence of soil bacteria alone (treatment 2): The error bars in treatments 2 and 4 do not overlap, which means that the differences between the two data sets are statistically significant. Thus, AM fungi significantly increases yellow bedstraw growth when these plants are exposed to soil bacteria.

Owls (primary predators of rock pocket mice) are nocturnal visual predators that are able to distinguish effectively between dark and light colors in low-light conditions. Which of the following best explains the relationship between coat color and predation rate in the rock pocket mouse population on the lava flow rocks with respect to the different coat color phenotypes?

A dark coat color provides camouflage to mice on the lava flow rocks; therefore, mice with dark coats have a lower predation rate in that habitat.

A molecule with negative charges interacts with positively charged side chains in the enzyme's active site.

Researchers have discovered details about apoptosis (programmed cell death) by studying embryologic development of a nematode worm, Caenorhabditis elegans. Apoptosis is a normal developmental process in C. elegans. They found several genes involved in apoptosis, including ced−9 and ced−3 . The ced−3 gene was found to promote cell death, and ced−9 to inhibit it. The ced−9 gene serves as a regulator that prevents apoptosis in the absence of a signal promoting apoptosis. Which of the following statements best justifies the claim that changes in the expression of ced−9 in C. elegans can affect regulation of apoptosis in the cell? A) An experiment showed that a mutation in the ced−9 gene led to excessive cell death in C. elegans. B) An experiment showed that the ced−9 gene normally produces a protein that promotes excessive cell death in C. elegans. C) A mutation in ced−3 will cause ced−9 to be incorrectly transcribed. D) Apoptosis is dependent on a signal from the ced−9 gene in C. elegans.

A) An experiment showed that a mutation in the ced−9 gene led to excessive cell death in C. elegans.

A) An experiment showed that a mutation in the ced−9ced−9 gene led to excessive cell death in C. elegans.

Based on Figure 1-3, which statement describes how water is pulled up through the xylem to the leaves of the plant? A) As water exits the leaf, hydrogen bonding between water molecules pulls more water up from below. B) As water exits the leaf, signals are sent to the roots to pump more water up to the leaves through the xylem by adhesion. C) Evaporation from the leaf decreases the hydrogen bonds that form between the water molecules in the xylem, which helps the water molecules to be pulled up the xylem. D) Evaporation of water from the leaf increases the hydrogen bonds that form between water molecules in the air, providing the energy for transport.

A) As water exits the leaf, hydrogen bonding between water molecules pulls more water up from below.

During a fight-or-flight response, epinephrine is released into the body's circulatory system and transported throughout the body. Some cells exhibit a response to the epinephrine while other cells do not. Which of the following justifies the claim that differences in components of cell signaling pathways explain the different responses to epinephrine? A) Cell signaling depends on the ability to detect a signal molecule. Not all cells have receptors for epinephrine. Only cells with such receptors are capable of responding. B) Cell signaling depends on the transduction of a received signal by the nervous system. Not all cells are close enough to a synapse to receive the signal and respond. C) Cell signaling depends on the signal being able to diffuse through the cell membrane. Epinephrine is incapable of diffusing through some plasma membranes because of the membrane's phospholipid composition. D) Cell signaling requires reception, transduction, and response. All cells can receive epinephrine, all cells respond with a pathway, but only select cells have the proper coding in their DNA to respond.

A) Cell signaling depends on the ability to detect a signal molecule. Not all cells have receptors for epinephrine. Only cells with such receptors are capable of responding.

An antigen can induce an immune response in a host organism. Antigens are targeted by antibodies that are produced by the organism's immune system in response to contact with the antigen. Antibodies are specific to antigens. Many different cell types are involved in immune responses. Which of the following best describes the role of cell-to-cell communication during a response to an invasion of antigens? A) Chemicals that are secreted from antigen-presenting cells then activate helper T cells. B) A macrophage cell engulfs a pathogen in the blood. C) Antigens attaching to receptors on memory B cells stimulate the memory B cells to become plasma cells. D) Antigen-presenting cells engulf antigens at the first exposure.

A) Chemicals that are secreted from antigen-presenting cells then activate helper T cells.

An antigen can induce an immune response in a host organism. Antigens are targeted by antibodies that are produced by the organism's immune system in response to contact with the antigen. Antibodies are specific to antigens. Many different cell types are involved in immune responses. Which of the following best describes the role of cell-to-cell communication during a response to an invasion of antigens? A) Chemicals that are secreted from antigen-presenting cells then activate helper T cells. B) A macrophage cell engulfs a pathogen in the blood. C) Antigens attaching to receptors on memory B cells stimulate the memory B cells to become plasma cells. D)vAntigen-presenting cells engulf antigens at the first exposure.

A) Chemicals that are secreted from antigen-presenting cells then activate helper T cells.

Based on Figure 5-3, which of the following questions could best be addressed? A) Does synapsis of homologous chromosomes in the parent cell contribute to an increase in genetic diversity in the daughter cells? B) Do sister chromatids separate and form diploid daughter cells? C) Do chromatids from nonhomologous chromosomes rearrange to produce identical daughter cells? D) Does synapsis of homologous chromosomes produce daughter cells that are identical to the parent cell?

A) Does synapsis of homologous chromosomes in the parent cell contribute to an increase in genetic diversity in the daughter cells?

Researchers investigated the effect of urea on the three-dimensional structure of a certain enzyme. The researchers dissolved the enzyme in an aqueous buffer solution and added urea to the solution. The enzyme did not appear to have a secondary or tertiary structure. The researchers carefully removed the urea from the solution and determined that the enzyme had the original secondary and tertiary structure again. Based on the results of the experiment, which of the following statements best predicts the effect of urea on the enzyme's function? A) Function will be disrupted by adding the urea and regained by removing the urea. B) Function will be disrupted by adding the urea, but it will not be regained by removing the urea. C) Function will be gained by adding the urea and disrupted by removing the urea. D) Function will be unaffected by the addition and removal of the urea.

A) Function will be disrupted by adding the urea and regained by removing the urea.

Based on Figure 3-1, which of the following statements best predicts the effect that a change from a moderately acidic environment (pH near 6) to a basic environment will have on peroxidase activity? A) Peroxidase activity will decrease. B) Peroxidase activity will increase. C) Peroxidase activity will stay the same D) Peroxidase activity will increase at first and then decrease

A) Peroxidase activity will decrease.

Based on Figure 1-8, How might this change affect the structure and function of the protein? A) The R-Group of the new amino acid, valine, has different chemical properties than the R-group of cysteine. This will cause the protein to misfold and not function properly in the cell. B) The new amino acid, valine, has replaced cysteine in the new protein. Since the number of amino acids has remained the same, there will be mo change in the three-dimensional folding, or function, of the protein. C) Since this is a linear section, it does not influence protein folding. Thus, there will be no change in protein structure or function. D) since the new amino acid is bounded on one side by an amino acid with a negatively charged R-group and by an amino acid on the other side with a positively charged R-group, the charges will balance and the protein will fold as usual.

A) The R-Group of the new amino acid, valine, has different chemical properties than the R-group of cysteine. This will cause the protein to misfold and not function properly in the cell.

Acetylcholinesterase (AChE) is a protein that catalyzes the conversion of acetylcholine to acetate and choline. When the concentration of AChE in an aqueous solution is held constant, the rate of the reaction catalyzed by AChE increases with increasing concentrations of substrate. At low concentrations of acetylcholine, a small increase in the substrate concentration results in a large increase in the reaction rate. At high concentrations of acetylcholine, however, a large increase in the substrate concentration results in only a small increase in the reaction rate. Which of the following statements correctly explains the observed effect of the acetylcholine concentration on the rate of the enzyme-catalyzed reaction? A) The active site of AChE is specific for acetylcholine, and only one substrate molecule can occupy the active site at a time. B) AChE begins converting product into substrate as the acetylcholine concentration changes from low to high. C) The AChE protein becomes denatured as the acetylcholine concentration changes from low to high. D) The substrate specificity of AChE changes as the acetylcholine concentration changes from low to high.

A) The active site of AChE is specific for acetylcholine, and only one substrate molecule can occupy the active site at a time.

Based on the information provided (Figure 1-2 and Table 1-1), which of the following statements best describes why starch and cellulose provide different functions in plants? A) The differences in the assembly and organization of the monomers of these two polymers result in different chemical properties. B) Since starch and cellulose are composed of identical monomers, the cellular environment where they are located controls their function. C) The monomers of cellulose are connected by covalent bonds, making it ideal for structural support. D) The monomers of starch are connected by ionic bonds, making ideal for energy storage for plants.

A) The differences in the assembly and organization of the monomers of these two polymers result in different chemical properties.

Fibroblast growth factor receptors (FGFRs) are transmembrane proteins that regulate cellular processes such as cell proliferation and differentiation. The extracellular domains of FGFR proteins bind specifically to signaling molecules called fibroblast growth factors. The intracellular domains of FGFR proteins function as protein kinases, enzymes that transfer phosphate groups from ATP to protein substrates. FGFR activation occurs when binding by fibroblast growth factors causes FGFR proteins in the plasma membrane to become closely associated with each other. The association of two FGFR proteins stimulates protein kinase activity, which triggers the activation of intracellular signaling pathways. A simplified model of FGFR activation is represented in Figure 1. Which of the following changes in the FGFR signaling pathway is most likely to result in uncontrolled cell proliferation? A) The irreversible association of FGFR proteins B) The loss of the FGFR protein kinase function C) A decrease in the intracellular concentration of ATP D) A decrease in the extracellular concentrations of fibroblast growth factors

A) The irreversible association of FGFR proteins

Adjacent plant cells have narrow channels called plasmodesmata that pass through the cell walls of the connected cells and allow a cytoplasmic connection between the cells. Which of the following statements best describes a primary function of plasmodesmata? A) They allow the movement of molecules from one cell to another, enabling communication between cells. B) They prevent the cell membrane from pulling away from the cell wall during periods of drought. C) They eliminate the need to produce signaling molecules and eliminate the need for cells to have receptors for signaling molecules. D) They increase the surface area available for attachment of ribosomes and thus increase protein synthesis.

A) They allow the movement of molecules from one cell to another, enabling communication between cells.

Based on the data from graph 3-1, scientists claim that the reproductive behavior of European flycatchers is influenced by the availability of energy sources. Which of the following statements best justifies this claim? A) Young European flycatchers hatch from eggs when caterpillar biomass is available for the young birds to consume and convert into energy for growth. B) European flycatcher hatchlings begin to need energy to leave the nest only after the caterpillars have turned into pupae. C) Female European flycatchers require energy to lay eggs, so they lay their eggs when the caterpillar biomass is maximal. D) The energy requirements for hatching European flycatchers and caterpillars are proportional to each other.

A) Young European flycatchers hatch from eggs when caterpillar biomass is available for the young birds to consume and convert into energy for growth.

The MPF protein complex turns itself off by

A) activating a process that destroys cyclin components

For this condition, which of the following modes of inheritance is most consistent with the observations based on Figure 5-5? A) autosomal dominant B) Autosomal Recessive C) X-linked dominant D) X-linked recessive

A) autosomal dominant

A set of five additional test tubes were prepared and used as controls. Which of the following best describes the contents expected to be contained in one of the five control test tubes based on Figure 3-2? A) pH 4 buffer solution and hydrogen peroxide only B) All five pH buffer solutions combined and hydrogen peroxide only. C) Water, hydrogen peroxide, and yeast D) Water and yeast only

A) pH 4 buffer solution and hydrogen peroxide only

If you were able to walk into an opening cut into the center of a large redwood tree, when you exit from the middle of the trunk (stem) outward, you would cross, in order,

A) the annual rings, phloem, and bark.

Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, taxol disrupts microtubule formation by binding to microtubules and accelerating their assembly from the protein precursor, tubulin. Surprisingly, this stops mitosis. Specifically, taxol must affect

A) the fibers of the mitotic spindle.

Figure 1. Comparison of observations of selected mammals in 1996 and 2011. Figure 2. Change in host preference by Culex cedecei between 1979 and 2016. Based on the data, which of the following most accurately matches a potential change with its predicted effects on the southern Florida ecosystem?

A. Introduction of a new top predator species that preys solely on Burmese pythons would cause an increase in the raccoon population.

In vascular plants, water flows from root to leaf via specialized cells called xylem. Xylem cells are hollow cells stacked together like a straw. A student explains that evaporation of water from the leaf pulls water up from the roots through the xylem, as shown in Figure 1. Which statement describes how water is pulled up through the xylem to the leaves of the plant?

A. As water exits the leaf, hydrogen bonding between water molecules pulls more water up from below.

If an enzyme in solution is saturated with substrate, the most effective way to obtain a faster yield of products is to

Add more of the enzyme

Figure 1 shows three amino acids that are part of a polypeptide chain. Figure 2 shows the same section of the chain after a mutation has occurred. How might this change affect the structure and function of the protein?

A. The R-group of the new amino acid, valine, has different chemical properties than the R-group of cysteine. This will cause the protein to misfold and not function properly in the cell.

Different polysaccharides are used by plants for energy storage and structural support. The molecular structures for two common polysaccharides are shown in Figure 1. Starch is used by plants for energy storage, and cellulose provides structural support for cell walls. The monomer used to construct both molecules is glucose. A study determined the effect of two different digestive enzymes, A and B, on these two polysaccharides. Table 1 presents the data from the study. Mammals do not produce digestive enzyme B. However, sheep and cattle are two types of mammals that contain microorganisms in their digestive tract that produce enzyme B. Based the information provided, which of the following statements best describes why starch and cellulose provide different functions in plants?

A. The differences in the assembly and organization of the monomers of these two polymers result in different chemical properties.

A researcher claims that a certain herbicide suppresses plant growth by inhibiting chloroplast function. Which of the following statements best clarifies how the data supports the researchers claim?

ATP synthase activity depends on a proton gradient across the thylakoid membrane.

Which of the following did the results of Stanley Miller's experiments support?

Abiotic synthesis of organic compounds, possible first stage in the origin of life, and mechanism.

A study was conducted to understand the factors controlling the rate at which molecules or ions travel across cell membranes. An artificial membrane was created that was composed of a phospholipid bilayer only. The speed at which various substances crossed this membrane was measured. Some substances can pass through an actual cell membrane much faster than they passed through the artificial membrane in this study. Which of the following statements best explains this finding?

Actual cell membranes have a variety of proteins embedded in the membrane that are absent in the artificial membrane.

What is Gregor Mendel's contribution to the history and study of genetics? A. He discovered that characteristics are determined by inherited factors (genes). B. All of the other answer choices C. He discovered that alleles can be dominant or recessive. D. He discovered that alleles segregate independently during the formation of gametes.

All of the other answer choices

Taq polymerase

Allows reaction mixture to be repeatedly heated without destroying enzyme activity

Misfolding of polypeptides is a serious problem in cells. Which of the following diseases are associated with an accumulation of misfolded polypeptides?

Alzheimer's and Parkinson's only

Huntington's disease has been traced to the number of CAG repeats in the HTT gene, which is located on chromosome 4. The phenotypic influence of individual alleles with different numbers of repeats is shown in Table 1. Which of the following is most likely the immediate cause of the first appearance of Huntington's disease in a person?

An allele with more than 39 CAGCAG repeats was inherited by the affected person.

Based on the information presented, how does aldosterone most likely enter target cells?

By simple diffusion.

Based on the data in Table 4-3, the percent of the mitotic cells that were in metaphase is closest to which of the following? A) 5% B) 11% C) 18% D) 66%

Answer C C) 18%

Which of the following statements is a correct distinction between autotrophs and heterotrophs?

Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.

11) Prokaryotes are classified as belonging to two different domains. What are the domains? A) Bacteria and Eukarya B) Bacteria and Archaea C) Archaea and Protista D) Bacteria and Protista

11. Which of the following correctly describes a possible polygenic genotype of an organism? a. XX b. AaBbCC c. Alive d. Dead e. Orange

13) Which of the following is present in a prokaryotic cell? A) mitochondrion B) ribosome C) chloroplast D) ER

2. A human cell undergoes meiosis. How many chromosomes will each daughter cell have? a. 12 b. 23 c. 46 d. 92 e. None of the above

20. The fact that alleles of genes get sorted into gametes independently of each other is known as what? a. Law of Segregation b. Law of Independent Assortment c. Crossing over d. Polar bodies e. Zygote

21) A cell with a predominance of free ribosomes is most likely _____. A) primarily producing proteins for secretion B) primarily producing proteins in the cytosol C) constructing an extensive cell wall or extracellular matrix D) enlarging its vacuole

21. A heterozygous type A mother crosses with a heterozygous type B father. What is the likelihood that their offspring will be type AB? a. 0% b. 25% c. 50% d. 75% e. 100%

22) Which organelle often takes up much of the volume of a plant cell? A) lysosome B) vacuole C) Golgi apparatus D) peroxisome

23) A cell with an extensive area of smooth endoplasmic reticulum is specialized to _____. A) play a role in storage B) synthesize large quantities of lipids C) actively export protein molecules D) import and export protein molecules

26) The difference in lipid and protein composition between the membranes of the endomembrane system is largely determined by the _____. A) transportation of membrane lipids among the membranes of the endomembrane system by small membrane vesicles B) function of the Golgi apparatus in sorting and directing membrane components C) modification of the membrane components once they reach their final destination D) synthesis of different lipids and proteins in each of the organelles of the endomembrane system

29) The liver is involved in detoxification of many poisons and drugs. Which of the following structures is primarily involved in this process and, therefore, abundant in liver cells? A) rough ER B) smooth ER C) Golgi apparatus D) nuclear envelope

3) In the fractionation of homogenized cells using centrifugation, the primary factor that determines whether a specific cellular component ends up in the supernatant or the pellet is the _____. A) relative solubility of the component B) size and weight of the component C) percentage of carbohydrates in the component D) presence or absence of lipids in the component

30. Why are mtDNA and cpDNA mutations rare? a. They are inherited through one parent - the father b. They are inherited through one parent - the mother c. They are inherited through both parents - any mutations possible are shadowed by functional genes d. They are not inherited by any of the parents - mutations can not be passed down e. None of the above

34) Which organelle is the primary site of ATP synthesis in eukaryotic cells? A) lysosome B) mitochondrion C) Golgi apparatus D) peroxisome

4. What stage of meiosis does independent assortment occur? a. Prophase I b. Metaphase I c. Anaphase I d. Telophase I e. Cytokinesis I

44) Which of the following contain the 9 + 2 arrangement of microtubules, consisting of nine doublets of microtubules surrounding a pair of single microtubules? A) motile cilia and primary (nonmotile) cilia B) flagella and motile cilia C) basal bodies and primary (nonmotile) cilia D) centrioles and basal bodies

56) Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells? A) desmosomes B) gap junctions C) extracellular matrix D) tight junctions

6) A newspaper ad for a local toy store indicates that an inexpensive toy microscope available for a small child is able to magnify specimens nearly as much as the more costly microscope available in your college lab. What is the primary reason for the price difference? A) The toy microscope does not have the same fine control for focus of the specimen. B) The toy microscope magnifies a good deal, but has low resolution and therefore poor quality images. C) The college microscope produces greater contrast in the specimens. D) The toy microscope usually uses a different wavelength of light source.

62) Both the volume and the surface area for three different cells were measured. These values are listed in the following table: Volume Surface Area Cell 1 9.3 μm3 26.5 μm2 Cell 2 12.2 μm3 37.1 μm2 Cell 3 17.6 μm3 40.6 μm2 Using data from the table above, select the best explanation for why that cell will be able to eliminate waste most efficiently? A) Cell 1 since it has the smallest volume and will not produce as much waste as the other cells. B) Cell 2 since it has the highest surface areatovolume ratio which facilitates the exchange of materials between a cell and its environment. C) Cell 3 since it has the largest surface area which will enable it to eliminate all of its wastes quickly. D) Cell 3 because it is big enough to allow wastes to easily diffuse through the plasma membrane.

7. Which of the following pairs of alleles shows a heterozygous pair? a. XX b. Xx c. xx d. All of the above e. None of the above

9) Which of the following is a major difference between prokaryotic cells and eukaryotic cells? A) Prokaryotes have cells while eukaryotes do not. B) Eukaryotic cells have more intracellular organelles than prokaryotes. C) Prokaryotes are not able to carry out aerobic respiration, relying instead on anaerobic metabolism. D) Prokaryotes are generally larger than eukaryotes.

A researcher claims that spinach leaves capture the most energy from light waves in the range of 500 nm to 600 nm. To test the claim, the researcher will place spinach leaves in separate chambers and expose the leaves to different wavelengths of light. For each chamber, the researcher will measure the amount of oxygen gas (O2) that is produced in one hour. Which of the following graphs best represents data from the experiment that will support the researcher's claim?

Anthony is an adolescent who has a pimple on his cheek and thinks everyone is looking at it. Which of the following best explains what Anthony is experiencing? (A) the personal fable phenomenon (B) the imaginary audience phenomenon (C) moratorium (D) identity foreclosure (E) identity diffusion

Becky just watched a video of a child hitting a doll. According to Albert Bandura's research, Becky will now (A) get a second doll (B) hit her own doll (C) hug her doll (D) hide her doll (E) stop playing with her doll

Cheryl has difficulty making friends. She frequently argues with her peers and is mean to them. Her poor peer relationships can be explained by the fact that (A) she has a strong identity (B) she has a tense relationship with her parents (C) she is identity foreclosed (D) she is experiencing adolescent egocentrism (E) her cerebellum is not fully developed so she is overly emotional

Five dialysis bags, constructed from a semipermeable membrane that is impermeable to sucrose, were filled with various concentrations of sucrose and then placed in separate beakers containing an initial concentration of 0.6 M sucrose solution. At 10-minute intervals, the bags were massed (weighed) and the percent change in mass of each bag was graphed. Which line or lines in the graph represent(s) bags that contain a solution that is hypertonic at 50 minutes?

It is not possible to randomly assign the participants in Lawrence Kohlberg's studies on moral development into groups because (A) Kohlberg did not believe there were distinct stages of moral development (B) Kohlberg compared people of different ages (C) deception would be necessary (D) it would be unethical (E) his research would then not be generalizable to groups other than men

The mechanism of action of many common medications involves interfering with the normal pathways that cells use to respond to hormone signals. Which of the following best describes a drug interaction that directly interferes with a signal transduction pathway? A A medication causes the cell to absorb more of a particular mineral, eventually poisoning the cell. B A medication enters the target cell and inhibits an enzyme that normally synthesizes a second messenger. C A medication enters the target cell's nucleus and acts as a mutagen. D A medication interrupts the transcription of ribosomal RNA genes.

B A medication enters the target cell and inhibits an enzyme that normally synthesizes a second messenger.

In mammals, an increase in the concentration of sodium in the blood triggers the release of antidiuretic hormone (ADH) from the pituitary gland. As the concentration of sodium in the blood returns to previous levels, the release of ADH from the pituitary gland is reduced. Based on the information presented, which of the following describes the most likely role of ADH in maintaining blood osmolarity? A ADH promotes an increase in the movement of sodium into the bloodstream. B ADH promotes an increase in the movement of water into the bloodstream. C ADH promotes an increase in the excretion of water from the body. D ADH promotes an increase in the secretion of additional ADH from the pituitary gland.

B ADH promotes an increase in the movement of water into the bloodstream.

The endocrine system incorporates feedback mechanisms that maintain homeostasis. Which of the following demonstrates negative feedback by the endocrine system? A During labor, the fetus exerts pressure on the uterine wall, inducing the production of oxytocin, which stimulates uterine wall contraction. The contractions cause the fetus to further push on the wall, increasing the production of oxytocin. B After a meal, blood glucose levels become elevated, stimulating beta cells of the pancreas to release insulin into the blood. Excess glucose is then converted to glycogen in the liver, reducing blood glucose levels. C At high elevation, atmospheric oxygen is more scarce. In response to signals that oxygen is low, the brain decreases an individual's rate of respiration to compensate for the difference. D A transcription factor binds to the regulatory region of a gene, blocking the binding of another transcription factor required for expression.

B After a meal, blood glucose levels become elevated, stimulating beta cells of the pancreas to release insulin into the blood. Excess glucose is then converted to glycogen in the liver, reducing blood glucose levels.

The model shown in the figure represents the role of two hormones, calcitonin and parathyroid hormone (PTH), in maintaining normal blood calcium levels in humans. If a dietary change results in an increase in blood calcium concentration above normal levels, which of the following is the most likely effect on calcium homeostasis? A Calcitonin levels will decline, thus stimulating the release of PTH. B Calcitonin levels will rise, thus promoting the deposit of calcium into bones. C PTH levels will decline, thus stimulating the loss of calcium from bones. D PTH levels will increase, thus preventing the release of calcitonin.

B Calcitonin levels will rise, thus promoting the deposit of calcium into bones.

Students in a class measured the mass of various living organisms. They then kept the organisms in the dark for 24 hours before remeasuring them. None of the organisms were provided with nutrients during the 24-hour period. The data are as follows. Which of the following is the best explanation for the pattern of change in mass of the organisms over time? A Water loss due to evaporation B Cellular respiration C The law of conservation of matter D Growth and reproduction

B Cellular respiration

The chemical reaction for photosynthesis is 6 CO2 + 12 H2O + light energy → C6H12O6 + 6 O2 + 6 H2O If the input water is labeled with a radioactive isotope of oxygen, 18O, then the oxygen gas released as the reaction proceeds is also labeled with 18O. Which of the following is the most likely explanation? A During the light reactions of photosynthesis, water is split, the hydrogen atoms combine with the CO2, and oxygen gas is released. B During the light reactions of photosynthesis, water is split, removing electrons and protons, and oxygen gas is released. C During the Calvin cycle, water is split, regenerating NADPH from NADP+, and oxygen gas is released. D During the Calvin cycle, water is split, the hydrogen atoms are added to intermediates of sugar synthesis, and oxygen gas is released.

B During the light reactions of photosynthesis, water is split, removing electrons and protons, and oxygen gas is released.

Which of the following questions will best direct an investigation of the mechanism of ATP synthase? A What is the source of the inorganic phosphate that is used to generate ATP from ADP? B Is the phosphorylation of ADP by ATP synthase dependent on the formation of a proton gradient? C Can ATP synthase use the energy released by phosphorylation of ADP to pump protons against a concentration gradient? D Can oxidative phosphorylation be uncoupled from the electron transport chain?

B Is the phosphorylation of ADP by ATP synthase dependent on the formation of a proton gradient?

For following group of questions first study the description of the situation and diagrams and then choose the one best answer to each question following it and fill in the corresponding oval on the answer sheet. A student studied the effects of light intensity on oxygen production in green algae. The algae were suspended in water inside a sealed glass jar, and the jar was placed into a constant-temperature, lightproof box containing a light source. A probe was inserted into the jar to record the concentration of oxygen. The probe was connected to a recording device. The setup is shown below. The student decreased the intensity of the light hourly and recorded the corresponding changes in oxygen concentration. The graph below shows the results from the recording device. Based on the data shown, changes in the light intensity resulted in changes in the rate of which of the following processes? A Excretion B Photosynthesis C Respiration D Translation E Transcription

B Photosynthesis

The figure above shows an organelle typically found in eukaryotic cells. Which of the following best describes the function of the double membrane system of this organelle? A The outer membrane allows the transport of all molecules into the intermembrane space, while the inner membrane serves as the regulatory boundary. B The inner membrane has specialized proteins that create a hydrogen ion concentration gradient between the intermembrane space and the matrix. C The outer membrane contains transport proteins that establish a sodium ion concentration gradient used for ATP production, while the inner membrane contains transport proteins that establish a hydrogen ion concentration gradient used for glucose production. D The toxins and wastes entering a cell cross the outer membrane and are detoxified by digestive enzymes stored within the intermembrane space.

B The inner membrane has specialized proteins that create a hydrogen ion concentration gradient between the intermembrane space and the matrix.

A researcher suggests that the Irish monoculture (growing a single crop) of the Lumper potato did not significantly change the overall resistance of the potato crop in Ireland to diseases. Which of the following observations best refutes this null hypothesis?

B The number of fatalities from the Irish potato famine was greater than the rest of the European countries combined.

For following group of questions first study the description of the data and then choose the one best answer to each question following it and fill in the corresponding oval on the answer sheet. To study the actions of the enzyme catalase on hydrogen peroxide, students performed the following experiment. Catalase was extracted from potatoes by blending raw potatoes in a blender with cold distilled water. The filtrate was stored on ice. The following hydrogen peroxide solutions were made: 1 percent, 5 percent, 10 percent, and 15 percent. Filter paper disks were soaked in the catalase filtrate and dropped into beakers containing the various solutions. The activity of the enzyme was measured by the amount of time it took for the disks to float to the surface of the solution on the bubbles produced by the reaction. The following data were obtained. Which of the following best describes why ice was used during this experiment? A To increase the activity of the enzyme B To retard the breakdown of the catalase C To purge the solution of excess air trapped during blending D To slow the catalase molecules to increase the probability of contact with the hydrogen peroxide molecules E To increase the size of the active site on the enzyme

B To retard the breakdown of the catalase

Directions: Each group of questions below concerns an experimental or laboratory situation or data. In each case, first study the description of the situation or data. Then choose the one best answer to each question following it. A tissue culture of vertebrate muscle was provided with a constant excess supply of glucose under anaerobic conditions starting at time zero and the amounts of pyruvic acid and ATP produced were measured. The solid line in the graph above represents the pyruvic acid produced in moles per liter per minute. ATP levels were also found to be highest at points A and C, lowest at B and D. A second culture was set up under the same conditions, except that substance X was added, and the results are indicated by the dotted line. It is most reasonable to hypothesize that, in the breakdown of glucose, substance X is A an activator B an inhibitor C a substrate D a coenzyme E a cofactor

B an inhibitor

A scientist determined the rate of an enzyme-catalyzed reaction by measuring the amount of product formed over time. The following curve was generated from the data collected. The rate of the reaction could also be determined by A measuring the change in the amount of enzyme B measuring the change in the amount of substrate C measuring the change in salt concentration D adding more substrate E adding more enzyme

B measuring the change in the amount of substrate

Related to Question 1 Information: Based on the data in the figure, a student claimed that since 2007, the carrying capacity of wolves in Yellowstone National Park has been 100 wolves, and the maximum annual per capita growth rate of gray wolves is 0.6 wolves per wolf per year. Which of the following is closest to the calculated wolf population size in 2017 based on the student's claim?

B = 103: According to the logistic growth model, the change in population size (dN/dt) can be calculated using the equation dN/dt=rmaxN((K−N)/K). According to the student's claim, rmax=0.6 wolves/year and K=100 wolves. From Figure 1, N=108 wolves in 2016. Therefore, dN/dt=0.6×108×((100−108)/100)=−5.184. The -5.184 needs to be added to the 2016 population size to get the population size for 2017: 108+(−5.184)=102.816108+(−5.184)=102.816, which is rounded to 103 to get the final answer.

In the mid-1920s, gray wolves, Canis lupus, were eliminated from Yellowstone National Park in the northwestern United States. Over the course of 1995 and 1996, 31 wolves from Canada were relocated to the park. Researchers have tracked the growth of the wolf population from 21 in 1995 to 108 at the end of the study in 2016 (Figure 1). Figure 1. Yellowstone National Park annual wolf population from 1995 to 2016 The wolves prey on large herbivores, primarily elk. The carcasses of wolf kills are a valuable food source for coyotes, Canis latrans. When coyotes are feeding on carcasses, they may be chased off the carcass and/or killed by wolves. Coyotes also hunt small mammals for food. Researchers were studying the effect of wolves' presence on the behavior of coyotes. Researchers observed coyotes in a specific area of Yellowstone National Park and recorded the proportion of the coyotes' time spent on five different activities when wolves were present in the study area and when wolves were absent (Figure 2). Figure 2. Coyote behavior in the presence and absence of wolves. Error bars represent a confidence interval of 95% (±2 standard errors of the mean). Based on information in Figure 1, which of the following is closest to the annual growth rate of the wolf population in Yellowstone National Park from 1996 to 2004 ?

B = 17 wolves per year: The equation for calculating a rate is dY/dt, which is the difference in the variable on the y-axis divided by the difference in the variable on the x-axis. In this case, that equation becomes annual population growth rate = (final population size - initial population size)/(number of years). According to Figure 1, in 1996 the population was 36 wolves, and 8 years later, in 2004, the population was 171 wolves. Therefore, (171−36)/8=16.875, which can be rounded to 17 wolves per year.

Soluble reactive phosphate (SRP) is a term used to describe the amount of phosphate available for uptake by living things. A study of river plants species and water phosphate levels was completed in Great Britain. Recently, in a section of one of the rivers studied, a population of fennel-leaved pondweed was replaced by spiked water-milfoil, even though these two plants are associated with different environmental conditions as indicated in the table below. A group of researchers suggest that the concentration of available phosphate in this particular section of the British river does not have a significant impact on which plant species grow. Alternatively, another group of researchers hypothesize that levels of available phosphate do affect which plant species grow at this location. Which of the following observations would best support this alternative hypothesis?

B = Increased fertilizer use near this section of the river has led to increased runoff of phosphates into the river: Human activities such as the addition of organic or chemical fertilizers to lawns, golf courses, and agricultural lands and the observed increase in runoff of the phosphorus in these fertilizers into the rivers is the most likely contributor to the increased SRP level in the water that resulted in the change in plant species.

Meerkats live together in groups to help raise and protect their offspring. Meerkat pups are most vulnerable when they are away from their burrow foraging for food. Adult meerkats exhibit sentinel behavior, standing upright and making alarm calls to warn other members in the group that predators are nearby. In a study of meerkat behaviors, scientists observed meerkat foraging groups and recorded the presence or absence of pups along with the frequency of adult sentinel behavior. The scientists determined that sentinel behavior increased when pups were present in the foraging group. Which of the following correctly identifies the dependent and independent variables in the described study?

B = The presence of pups is the independent variable, and the frequency of sentinel behavior is the dependent variable: The scientists are studying the relationship between the presence of pups (independent variable) and the frequency of sentinel behavior (dependent variable).

Bt corn varieties are genetically modified to produce a toxin that specifically kills corn borers, a type of insect that eats and damages corn crops. Insects that are not closely related to corn borers are not affected by the toxin. Figure 1 shows the increasing production of Bt corn varieties and the change in the use of broad-spectrum pesticides that were the primary means of killing corn borers before the invention of Bt corn. Figure 1. Relative use of pesticides on corn fields and percent of Bt corn in crops How do the data in Figure 1 support the alternative hypothesis that increased use of Bt corn reduces the impact of corn farming on the natural environment?

B = The toxin in Bt corn kills only the corn pests, leaving other insects unharmed: Bt corn is modified to be toxic to certain insects; thus, it doesn't require as much insecticide. The graph shows this trend.

The marine iguana, Amblyrhynchus cristatus, is endemic to the Galápagos Islands and is especially vulnerable to El Niño events. These iguanas feed on red and green algae. During an El Niño climate event, surface waters and their currents in the central and eastern Pacific Ocean become significantly warmer than usual. Also during El Niño years, land masses experience increased rainfall. A researcher suggests that El Niño conditions cause a significant decrease in the size of the Galápagos marine iguana population. Which of the following would best support this alternative hypothesis?

B = Warm surface water contains fewer nutrients needed by red and green algae than cooler surface waters does: Upwelling brings cold, nutrient-rich waters to the surface. During El Niño years this is inhibited, so algae populations decrease because nutrients are limiting, resulting in decreased marine iguana populations.

The students plan to use a significance level of p=0.01. Based on Table 5-4, which of the following is the most appropriate critical value for the students to use in their chi-square goodness-of-fit test? A) 7.82 B) 11.34 C) 13.28 D) 326.7

B) 11.34

Based on Figure 5-8, If the woman and a man with normal clotting function have children, what is the probability of their children exhibiting hemophilia A? A) 50 percent for daughters, 0 percent for sons B) 50 percent for sons, 0 percent for daughters C) 50 percent for all children D) 0 percent for all children

B) 50 percent for sons, 0 percent for daughters

A triploid cell contains three sets of chromosomes. If a cell of a usually diploid species with 42 chromosomes per cell is triploid, this cell would be expected to have which of the following?

B) 63 chromosomes in 21 sets of 3

Which of the following is closest to the calculated chi-square (χ2) value for the data presented in Table 5-2? A) 8,35 B) 72.01 C) 98.00 D) 2,546.00

B) 72.01

Based on Table 3-4, which of the following statements best clarifies how the data support the researcher's claim? A) The thylakoid membrane is more permeable to carbon dioxide than to polar molecules. B) ATP synthase activity depends on a proton gradient across the thylakoid membrane. C) Some enzymes embedded in the thylakoid membrane catalyze the hydrolysis of ATP. D) Carbon fixation in the Calvin-Benson cycle takes place in the stroma of chloroploasts.

B) ATP synthase activity depends on a proton gradient across the thylakoid membrane.

A student wants to modify model 1 so that it represents an RNA double helix instead of a DNA double helix. Of the following possible changes, which would be most effective in making model 1 look more like RNA than DNA? A) Changing the sequence of the base pairs B) Changing the deoxyriboses to riboses by adding -OH groups C) Changing the shpaes of the nitrogenous bases to match those shown in model 2-1. Changing the sugar-phosphate backbone to a ribbon, as shown in model 3-1

B) Changing the deoxyriboses to riboses by adding -OH groups

Signal transduction may result in changes in gene expression and cell function, which may alter phenotype in an embryo. An example is the expression of the SRY gene, which triggers the male sexual development pathway in mammals. This gene is found on the Y chromosome. Which statement provides the evidence to justify the claim that signal transduction may result in an altered phenotype? A) If the SRY gene is absent or nonfunctional, the embryo will exhibit male sexual development. B) If the SRY gene is absent or nonfunctional, the embryo will exhibit female sexual development. C) An embryo with a male sex chromosome will always exhibit male sexual development. D) An embryo with two male sex chromosomes will always exhibit male sexual development.

B) If the SRY gene is absent or nonfunctional, the embryo will exhibit female sexual development.

A person's blood glucose level fluctuates during the day, as represented in Figure 1. Two hormones, insulin and glucagon, are directly involved in regulating the blood glucose level to maintain a healthy level. Insulin acts to lower the blood glucose level, and glucagon acts to increase the blood glucose level. Which of the following best predicts what will happen to the blood glucose level if the person has another meal at 5 p.m.? A) Immediately after the meal, the blood glucose level will decrease because of the increase in glucagon levels. B) Immediately after the meal, the blood glucose level will increase, and then insulin will be secreted to counter the increase. C) Several hours after the meal, the blood glucose level will increase sharply because of an increase in the amount of glucagon secreted. D) The blood glucose level will not change after the 5 p.m. meal because the person has already consumed two meals and the blood glucose level has been adjusted to a steady-state level.

B) Immediately after the meal, the blood glucose level will increase, and then insulin will be secreted to counter the increase.

Which of the following best predicts what will happen to the blood glucose level if the person has another meal at 5 p.m. based on Figure 4-5? A) Immediately after the meal, the blood glucose level will decrease because of the increase in glucagon levels. B) Immediately after the meal, the blood glucose level will increase, and then insulin will be secreted to counter the increase. C) Several hours after the meal, the blood glucose level will increase sharply because of an increase in the amount of glucagon secreted. D) The blood glucose level will not change after the 5 p.m. meal because the person has already consumed two meals and the blood glucose level has been adjusted to a steady-state level.

B) Immediately after the meal, the blood glucose level will increase, and then insulin will be secreted to counter the increase.

The epidermal growth factor receptor EGFR is a cell surface receptor. When a growth factor binds to EGFR, the receptor is activated. The activated EGFR triggers a signal transduction pathway, which leads to increased frequency of cell division. Which of the following best predicts the effect of a mutation that causes EGFR to be active in the absence of a growth factor? A) Increased apoptosis will lead to abnormal growth of the tissue. B) Increased cell division will lead to the formation of a tumor. C) Cells will exit the cell cycle, entering a non-dividing G0 phase. D) Fewer cells will be in any of the stages of mitosis.

B) Increased cell division will lead to the formation of a tumor.

Metformin is a drug used to treat type 2 diabetes by decreasing glucose production in the liver. AMP-activated protein kinase (AMPK) is a major cellular regulator of glucose metabolism. Metformin activates AMPK in liver cells but cannot cross the plasma membrane. By blocking AMPK with an inhibitor, researchers found that AMPK activation is required for metformin to produce an inhibitory effect on glucose production by liver cells. Which of the following best describes the component that metformin represents in a signal transduction pathway that regulates glucose production in the liver? A) It is a secondary messenger that amplifies a signal through a cascade reaction. B) It is a ligand that activates the signal transduction pathway of the activation of AMPK. C) It is an allosteric regulator that binds to a crucial section of the DNA that makes the enzymes needed for glucose uptake. D) It is a competitive inhibitor that binds to glucose and prevents it from entering the cell.

B) It is a ligand that activates the signal transduction pathway of the activation of AMPK.

The relative amounts of DNA present in the nucleus of a cell at four different stages of the life cycle are shown in Figure 1. Based on Figure 1, which of the following statements correctly links a stage of the cell cycle with the event occurring at that stage? A) Stage I represents the G2 phase of the cell cycle. B) Synthesis of sufficient DNA for two daughter cells occurs in stage II. C) Stage III includes mitosis. D) The replication of genetic material occurs in stage IV.

B) Synthesis of sufficient DNA for two daughter cells occurs in stage II.

When a mustard plant seedling is transferred to an environment with higher levels of carbon dioxide, the new leaves have a lower stomata-to-surface-area ratio than do the seedling's original leaves. Which of the following best explains how the leaves from the same plant can have different stomatal densities when exposed to an elevated carbon dioxide level? A) Increased photosynthesis leads to larger leaves that need more stomata for photosynthesis, leading to an increase in stomatal density. B) Leaf growth is promoted through increased photosynthesis, but the genetically regulated rate of stomatal production is not altered, leading to a decrease in stomatal density. C) Leaf growth is inhibited by decreased photosynthesis, and the genetically regulated rate of stomatal production remains the same, leading to an increase in stomatal density. D) Leaf growth is inhibited by decreased photosynthesis, and the genetically regulated rate of stomatal production remains the same, leading to a decrease in stomatal density.

B) Leaf growth is promoted through increased photosynthesis, but the genetically regulated rate of stomatal production is not altered, leading to a decrease in stomatal density.

A researcher found a mutation that resulted in the PFK enzyme being unable to bind ATP to the allosteric site. Which of the following best predicts the effect of the mutation based on Figure 4-4? A) The activity of the enzyme will not be affected because the active site is not involved in substrate binding at the allosteric site. B) Negative feedback regulation does not occur, so the enzyme will be active when glycolysis is not needed. C) Positive feedback does not occur, and the activity of the enzyme will decrease when glycolysis is needed. D) The activity of the enzyme will fluctuate independent of the ATPATP concentration.

B) Negative feedback regulation does not occur, so the enzyme will be active when glycolysis is not needed.

Phosphofructokinase (PFK) is a key enzyme in glycolysis. ATP is one of the two substrates for the reaction catalyzed by PFK. ATP is also an allosteric regulator of PFK. Figure 1 shows the enzyme-substrate interactions of PFK. A researcher found a mutation that resulted in the PFK enzyme being unable to bind ATP to the allosteric site. Which of the following best predicts the effect of the mutation? A) The activity of the enzyme will not be affected because the active site is not involved in substrate binding at the allosteric site. B) Negative feedback regulation does not occur, so the enzyme will be active when glycolysis is not needed. C) Positive feedback does not occur, and the activity of the enzyme will decrease when glycolysis is needed. D) The activity of the enzyme will fluctuate independent of the ATPATP concentration.

B) Negative feedback regulation does not occur, so the enzyme will be active when glycolysis is not needed.

Glycolysis is a metabolic pathway that converts glucose into pyruvate and is observed in each of the three domains. The hexokinase family of enzymes is required during glycolysis to phosphorylate six-carbon sugars. Researchers designed a general hexokinase inhibitor that is effective in the neurons of rats. Which of the following best predicts the effect of adding this inhibitor to a culture of plant cells? A) Plant cells will be unaffected by the inhibitor as they do not perform glycolysis. B) Plant cells will be unable to perform glycolysis due to the inhibitor and will die. C) Plant cells will be unable to perform photosynthesis due to the inhibitor and will die. D) Plant cells will still be able to perform glycolysis since plant hexokinase is not structurally similar to animal hexokinase.

B) Plant cells will be unable to perform glycolysis due to the inhibitor and will die.

Based on Figure 1-2, which of the following best compares to the atomic structures of starch and cellulose? A) Starch is composed of carbon, hydrogen, and oxygen, while cellulose also contains nitrogen. B) Starch and cellulose are composed of repeating glucose monomers; however, in cellulose every other glucose monomer is rotated 180 degrees. C) Starch is composed of monomers that each have a CH2OH group, while cellulose only has a CH2OH group on every other monomer. D) Starch and cellulose are composed of identical monomers and therefore have identical structures.

B) Starch and cellulose are composed of repeating glucose monomers; however, in cellulose every other glucose monomer is rotated 180 degrees.

Based on Figure 4-9, which of the following statements correctly links a stage of the cell cycle with the event occurring at that stage? A) Stage I represents the G2 phase of the cell cycle. B) Synthesis of sufficient DNA for two daughter cells occurs in stage II. C) Stage III includes mitosis. D) The replication of genetic material occurs in stage IV.

B) Synthesis of sufficient DNA for two daughter cells occurs in stage II.

Which of the follow indicates the mean number per cross of F2 plants producing medium-red grain and correctly explains the distribution of the phenotypes based on Table 5-7? A) The mean number of medium-red phenotypes per cross is 20.8. The distribution of phenotypes suggests that grain color is under environmental control. B) The mean number of medium-red phenotypes per cross is 20.8. The distribution of phenotypes suggests that multiple genes are involved in grain color determination. C) The mean number of medium-red phenotypes per cross is 104. The distribution of phenotypes suggests that grain color is under environmental control. D) The mean number of medium-red phenotypes per cross is 104. The distribution of phenotypes suggests that multiple genes are involved in grain color determination.

B) The mean number of medium-red phenotypes per cross is 20.8. The distribution of phenotypes suggests that multiple genes are involved in grain color determination.

Based on Figure 4-1, which of the following statements best predicts the effect of a loss of function of the insulin receptor's intracellular domain? A) The stimulation of the signal transduction pathway will increase. B) The storage of GLUT4 in vesicles inside the cell will increase. C) The number of GLUT4 molecules in the plasma membrane will increase. D) The concentration of glucose inside the cell will increase.

B) The storage of GLUT4 in vesicles inside the cell will increase.

The insulin receptor is a transmembrane protein that plays a role in the regulation of glucose homeostasis. The receptor's extracellular domain binds specifically to the peptide hormone insulin. The receptor's intracellular domain interacts with cellular factors. The binding of insulin to the receptor stimulates a signal transduction pathway that results in the subcellular translocation of GLUT4, a glucose transport protein that is stored in vesicles inside the cell. A simplified model of the insulin receptor-signaling pathway is shown in Figure 1. Which of the following statements best predicts the effect of a loss of function of the insulin receptor's intracellular domain? A) The stimulation of the signal transduction pathway will increase. B) The storage of GLUT4 in vesicles inside the cell will increase. C) The number of GLUT4 molecules in the plasma membrane will increase. D) The concentration of glucose inside the cell will increase

B) The storage of GLUT4 in vesicles inside the cell will increase.

Based on Figure 3-4, which of the following statements provides reasoning that supports the claim that brown fatty tissue keeps an animal warm? A) The uncoupling protein in this tissue increases the production of ATP and causes more body heat to be produced to warm the animal. B) The uncoupling protein in this tissue reduces the proton gradient across the membrane and thus produces heat to warm the animal without ATP production. C) The uncoupling protein in this tissue causes an increase in the proton gradient, which causes more ATP to be produced that helps to warm the animal. D) The uncoupling protein in this tissue reduces the production of ATP and creates an increase in the proton gradient that allows more heat energy to be produced to warm the animal.

B) The uncoupling protein in this tissue reduces the proton gradient across the membrane and thus produces heat to warm the animal without ATPATP production.

Which statement best predicts why a cell's progression through the cell cycle might be halted at the G1/S checkpoint? A) Spindle fibers have not correctly attached to chromosomes. B) There are not enough nucleotides available to construct new DNA. C) Damage occurred to DNA when it was being copied in G1G1. D) Proteins necessary for M phase of the cell cycle have not been produced.

B) There are not enough nucleotides available to construct new DNA.

Which statement best predicts why a cell's progression through the cell cycle might be halted at the G1/S checkpoint? A) Spindle fibers have not correctly attached to chromosomes. B) There are not enough nucleotides available to construct new DNA. C) Damage occurred to DNA when it was being copied in G1. D) Proteins necessary for M phase of the cell cycle have not been produced.

B) There are not enough nucleotides available to construct new DNA.

Which of the graphs below best represents the predicted change in mass over time of the dialysis bag in the beaker to which albumin was added?

B) slope stays constant then goes DOWN

If gastrulation was blocked by an environmental toxin, then

B) the blastula would not be formed.

Why do chromosomes coil during mitosis?

B) to allow the chromosomes to move without becoming entangled and breaking

A researcher claims that spinach leaves capture the most energy from light waves in the range of 500 nm to 600 nm. Which of the following graphs best represents data from the experiment that will support the researchers claim?

B) upside down U with peaks at 500-600

B)What is the length of the S phase of the cell cycle?

Figure 1. Average bottom light intensity in clipped plots versus enclosed plots Figure 2. Richness comparison of two treatments Which of the following statements is consistent with the data shown in the figures?

B. Different patterns of energy availability in ecosystems will affect species richness.

Figure 1. AIP cascade producing hemolysin toxin Identify the experimental design that would determine which AIP mimic would most effectively inhibit the production of hemolysin toxin.

B. Grow S. aureus in separate culture media containing one AIPAIP mimic each and measure the production of hemolysin toxin. The most effective AIPAIP mimic will be in the culture producing the lowest amount of hemolysin.

Scientists hypothesize that the invasive Burmese pythons are responsible for recent increases in human Everglades virus infections. Evaluate this alternate hypothesis using the data provided.

B. The alternate hypothesis is supported because the invasive Burmese pythons caused mosquitoes to switch to feeding on cotton rats. This means that mo

Which of the following correctly identifies the dependent and independent variables in this experiment? Table 1. Phototropic responses of plants to different colors of light

B. The percentage of plants showing phototropism is the dependent variable, and the color of the light is the independent variable.

A scientist interested in investigating how human population trends might affect local animal species' richness stipulates a null hypothesis that animal biodiversity in rural areas will be unaffected in the future by the human population trends shown in Figure 1. Which of the following would best refute this null hypothesis?

B. Urbanization causes habitat fragmentation.

The diagram above represents a model of signal transduction pathways (I and II) in a cell that is targeted by two different hormones (H1 and H2). The components of the signal transduction pathways are identified in the figure legend. Each cellular molecule in both pathways can exist in an inactive or active form. When the components in pathway I are sequentially activated, the TAP molecules promote cell division. When the components in pathway II are sequentially activated, downstream signaling by the G protein is inhibited. Based on the model, which of the following mutations is most likely to result in a cell that will generate a cancerous tumor? A. A mutation in the gene encoding PP that results in a nonfunctional protein B. A mutation in the gene encoding G-PIP that results in a nonfunctional protein C. A mutation in the gene encoding R1 so that it is inactive even in the presence of H1 D. A mutation in the gene encoding R2 so that it is active even in the absence of H2

B. A mutation in the gene encoding G-PIP that results in a nonfunctional protein

B. Changing the deoxyriboses to riboses by adding −OH groups

Ethylene is an organic compound produced by ripening fruits. In a controlled experiment, researchers found that ethylene gas stimulated the ripening process in newly harvested fruits. Which of the following describes the most likely connection between natural ethylene production and fruit ripening? A. As a result of metabolic inactivity, newly harvested fruits are unable to absorb ethylene gas from the atmosphere. B. Ethylene gas is a chemical signal through which ripening fruits trigger the ripening process in other fruits. C. Because of normal phenotypic variation, only some of the fruits in a given generation are expected to produce ethylene gas. D. The rate of ethylene gas production by ripening fruits is an indicator of the relative age of an ecosystem.

B. Ethylene gas is a chemical signal through which ripening fruits trigger the ripening process in other fruits.

The brain coordinates the circulatory and respiratory systems of the human body. The control of breathing, for example, involves neural pathways among the structures represented in the figure above. One important stimulus in the control of breathing is an increase in blood CO2 concentration, which is detected as a decrease in blood pH. Which of the following best describes the physiological response to an overall increase in cellular respiration in the body? A. In response to depleted blood CO2 levels, the pH sensors send signals directly to the rib muscles, resulting in an increase in the rate of CO2 uptake by the lungs and a decrease in CO2 utilization by the brain. B. In response to low blood pH, the pH sensors send a signal to the brain, which then sends a signal to the diaphragm, resulting in an increased rate of breathing to help eliminate excess blood CO2 . C. In response to high blood pH, the pH sensors send a signal directly to the lungs, resulting in a slower rate of breathing, and the lungs send a signal back to the heart once CO2 availability has been restored. D. In response to an increased rate of breathing, the rib muscles send a signal to the brain, which then sends a signal to the heart, resulting in a decrease in heart activity and slower flow of blood through the body.

B. In response to low blood pH, the pH sensors send a signal to the brain, which then sends a signal to the diaphragm, resulting in an increased rate of breathing to help eliminate excess blood CO2 .

Which of the following is true of mitosis? A. It is also known as cytokinesis. B. It maintains the same chromosome number in the daughter cells as in the parent cell. C. It is the last phase of interphase. D. It regulates the transfer of genetic information from one daughter cell to another. E. It moves homologous chromosomes to opposite poles.

B. It maintains the same chromosome number in the daughter cells as in the parent cell.

Different polysaccharides are used by plants for energy storage and structural support. The molecular structures for two common polysaccharides are shown in Figure 1. Starch is used by plants for energy storage, and cellulose provides structural support for cell walls. The monomer used to construct both molecules is glucose. A study determined the effect of two different digestive enzymes, A and B, on these two polysaccharides. Table 1 presents the data from the study. Mammals do not produce digestive enzyme B. However, sheep and cattle are two types of mammals that contain microorganisms in their digestive tract that produce enzyme B. Based on Figure 1, which of the following best compares the atomic structures of starch and cellulose?

B. Starch and cellulose are composed of repeating glucose monomers; however, in cellulose every other glucose monomer is rotated 180 degrees.

Which of the following statements best describes how a growth factor stimulates cell division from outside a cell? A. The growth factor binds to other cells in the same area and holds them together to form a large, multicellular structure. B. The growth factor binds to receptors on the cell surface, initiating a signal transduction pathway that activates specific target genes. C. The growth factor binds to sugar molecules in the extracellular fluid and provides them to the cell as a source of energy. D. The growth factor binds to phospholipids in the plasma membrane, creating a channel through which substances enter the cell.

B. The growth factor binds to receptors on the cell surface, initiating a signal transduction pathway that activates specific target genes.

One of the key research areas of the Human Genome Project was a new field of study called A. genetics. B. bioinformatics. C. pedigree. D. autosomes.

Bioinformatics

When scientists manipulate the genetic makeup of an organism, they are using A. bioinformatics. B. genomics. C. a pedigree. D. biotechnology.

Biotechnology.

Figure 1 represents a segment of DNA. Radiation can damage the nucleotides in a DNA molecule. To repair some types of damage, a single nucleotide can be removed from a DNA molecule and replaced with an undamaged nucleotide. Which of the four labeled bonds in Figure 1 could be broken to remove and replace the cytosine nucleotide without affecting the biological information coded in the DNA molecule?

Bonds Y and Z at the same time -By breaking bonds Y and Z at the same time, the cytosine nucleotide could be removed from the DNA molecule and replaced with an undamaged cytosine without changing the biological information stored in the DNA.

DNA polymerase

Build new DNA strand from a template, catalyzes the antiparallel elongation of the new DNA strands

A magnesium sulfate solution taken orally can cause a net movement of water into the large intestine, which results from water molecules diffusing through aquaporins embedded in the cells of the intestinal lining. By which of the following mechanisms do the water molecules most likely move into the large intestine?

By passive transport from an area of low osmolarity to an area of high osmolarity

Aldosterone (a steroid hormone) is a small, nonpolar, hydrophobic molecule that enters a target cell by moving across the plasma membrane, down a concentration gradient. Based on the information presented, how does aldosterone most likely enter target cells?

By simple diffusion

10) You have a cube of modeling clay in your hands. Which of the following changes to the shape of this cube of clay will decrease its surface area relative to its volume? A) Pinch the edges of the cube into small folds. B) Flatten the cube into a pancake shape. C) Round the clay up into a sphere. D) Stretch the cube into a long, shoebox shape.

12) Which structure is common to plant and animal cells? A) chloroplast B) central vacuole C) mitochondrion D) centriole

14) In a bacterium, we will find DNA in _____. A) a membraneenclosed nucleus B) mitochondria C) the nucleoid D) ribosomes

15) Which organelle or structure is absent in plant cells? A) mitochondria B) microtubules C) centrosomes D) peroxisomes

15. Crossing an organism with the genotype YyRr with an organism with the same genotype (YyRr) yields what ratio of phenotypes? a. 1:1:1:1 b. 1:2:2:1 c. 9:3:3:1 d. 6:4:4:2 e. 6:6:3:1

16. Recombination is most closely associated with what? a. Law of Segregation b. Law of Independent Assortment c. Crossing over d. Polar bodies e. Zygote

17) Which of the following macromolecules leaves the nucleus of a eukaryotic cell through pores in the nuclear membrane? A) DNA B) amino acids C) mRNA D) phospholipids

18) Which of the following statements correctly describes some aspect of protein secretion from prokaryotic cells? A) Prokaryotes cannot secrete proteins because they lack an endomembrane system. B) The mechanism of protein secretion in prokaryotes is probably the same as that in eukaryotes. C) Proteins secreted by prokaryotes are synthesized on ribosomes bound to the cytoplasmic surface of the plasma membrane. D) Prokaryotes cannot secrete proteins because they lack ribosomes.

19) Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules? A) lipids B) glycogen C) proteins D) nucleic acids

2) The advantage of light microscopy over electron microscopy is that _____. A) light microscopy provides for higher magnification than electron microscopy B) light microscopy provides for higher resolving power than electron microscopy C) light microscopy allows one to view dynamic processes in living cells D) light microscopy provides higher contrast than electron microscopy

28) TaySachs disease is a human genetic abnormality that results in cells accumulating and becoming clogged with very large, complex, undigested lipids. Which cellular organelle must be involved in this condition? A) the endoplasmic reticulum B) the Golgi apparatus C) the lysosome D) mitochondrion

28. A person's weight is an example of what? a. Continuous Generations b. Discontinuous Generations c. Continuous Variation d. Discontinuous Variation e. None of the above

30) Which of the following produces and modifies polysaccharides that will be secreted? A) lysosome B) mitochondrion C) Golgi apparatus D) peroxisome

31) What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell? A) ER → Golgi → nucleus B) Golgi → ER → lysosome C) ER → Golgi → vesicles that fuse with plasma membrane D) ER → lysosomes → vesicles that fuse with plasma membrane

33) Which of the following is NOT true? Both chloroplasts and mitochondria _____. A) have their own DNA B) have multiple membranes C) are part of the endomembrane system D) are capable of reproducing themselves

36) In a plant cell, DNA may be found _____. A) only in the nucleus B) only in the nucleus and chloroplasts C) in the nucleus, mitochondria, and chloroplasts D) in the nucleus, mitochondria, chloroplasts, and peroxisomes

39) Where are proteins produced other than on ribosomes free in the cytosol or ribosomes attached to the ER? A) in the extracellular matrix B) in the Golgi apparatus C) in mitochondria D) in the nucleolus

4) What is the reason that a modern transmission electron microscope (TEM) can resolve biological images to the subnanometer level, as opposed to tens of nanometers achievable for the best superresolution light microscope? A) The focal length of the electron microscope is significantly longer. B) Contrast is enhanced by staining with atoms of heavy metal. C) Electron beams have much shorter wavelengths than visible light. D) The electron microscope has a much greater ratio of image size to real size.

40) Suppose a cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from _____. A) a bacterium B) an animal but not a plant C) nearly any eukaryotic organism D) a plant but not an animal

43) Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures? A) membrane proteins of the inner nuclear envelope B) free ribosomes and ribosomes attached to the ER C) components of the cytoskeleton D) cellulose fibers in the cell wall

45) Vinblastine, a drug that inhibits microtubule polymerization, is used to treat some forms of cancer. Cancer cells given vinblastine would be unable to _____. A) form cleavage furrows during cell division B) migrate by amoeboid movement C) separate chromosomes during cell division D) maintain the shape of the nucleus

53) The cell walls of bacteria, fungi, and plant cells and the extracellular matrix of animal cells are all external to the plasma membrane. Which of the following is a characteristic common to all of these extracellular structures? A) They must block water and small molecules to regulate the exchange of matter and energy with their environment. B) They must provide a rigid structure that maintains an appropriate ratio of cell surface area to volume. C) They are constructed of polymers that are synthesized in the cytoplasm and then transported out of the cell. D) They are composed of a mixture of lipids and nucleotides.

60) H. V. Wilson worked with sponges to gain some insight into exactly what was responsible for holding adjacent cells together. He exposed two species of differently pigmented sponges to a chemical that disrupted the cellcell interaction (cell junctions), and the cells of the sponges dissociated. Wilson then mixed the cells of the two species and removed the chemical that caused the cells to dissociate. Wilson found that the sponges reassembled into two separate species. The cells from one species did not interact or form associations with the cells of the other species. How do you explain the results of Wilson's experiments? A) The two species of sponge had different enzymes that functioned in the reassembly process. B) The molecules responsible for cellcell adhesion (cell junctions) were irreversibly destroyed during the experiment. C) The molecules responsible for cellcell adhesion (cell junctions) differed between the two species of sponge. D) One cell functioned as the nucleus for each organism, thereby attracting only cells of the same pigment.

61) Gaucher disease is the most common of lipid storage diseases in humans. It is caused by a deficiency of an enzyme necessary for lipid metabolism. This leads to a collection of fatty material in organs of the body including the spleen, liver, kidneys, lungs, brain, and bone marrow. Using your knowledge of the structure of eukaryotic cells, identify the statement below that best explains how internal membranes and the organelles of cells would be involved in Gaucher disease. A) The mitochondria are most likely defective and do not produce adequate amounts of ATP needed for cellular respiration. B) The rough endoplasmic reticulum contains too many ribosomes which results in an overproduction of the enzyme involved in carbohydrate catalysis. C) The lysosomes lack sufficient amounts of enzymes necessary for the metabolism of lipids. D) The Golgi apparatus produces vesicles with faulty membranes that leak their contents into the cytoplasm of the cell.

Annette, who lives in the United States, experienced menarche at age ten, while her great-grandmother experienced it at age fourteen. Which of the following most likely explains the difference between the age that Annette and the age that her great-grandmother experienced menarche? (A) Annette's great-grandmother lived in a rural area, while Annette lives in a city. (B) Annette's great-grandmother was shorter than Annette. (C) Annette has better nutrition and medical care than her great-grandmother did. (D) Annette is the youngest child in her family, while her great-grandmother was the oldest child in her family. (E) Annette has more peers of the same age than her great-grandmother did.

Crystal has three children she loves and cares for very much. Denise has two children that she neglects. Crystal's children are very friendly and talk to people more often than Denise's children. Which of the following is the likely result of the children's attachment to their mothers? (A) Denise's children will have better identity formation. (B) Crystal used rewards and punishments more often than Denise. (C) Crystal's children will have better socialization skills. (D) Denise's children's schemas regarding parent-child relationships are quite strong (E) Crystal's children will have resolved the Oedipal complex, and Denise's children will not have.

Esther is looking back on her life and feels she has had a good life overall but that there are some things she could have done better. How would Erik Erikson explain Esther's thoughts? (A) She is starting to form her identity based on her past experiences. (B) She is experiencing proactive interference, which is causing her to reevaluate her life choices. (C) She is weighing whether she has succeeded in life, which is common in later adulthood. (D) She is reevaluating her life because she is following hypothetico-deductive thinking. (E) She is beginning to feel she can do things independently because she has had a good life.

Gender typing is best defined as (A) the belief or feeling that gender is constant throughout the life span (B) an overgeneralization about a group of people based on their gender (C) the process by which children become aware of their gender and thus behave accordingly by adopting attributes of members of the gender that they identify with (D) the development of an attraction or romantic relationship with people of a given gender or genders (E) a set of expectations about how people of certain genders should behave

Lawrence Kohlberg sampled 72 boys ages 10-16 years, the majority of whom he followed up with every 3 years for 20 years. He conducted interviews with the participants in which he presented them with a series of moral dilemmas. The participants judged the actions as right or wrong and provided their reasons for their decision. What type of research was Kohlberg conducting, and what were his findings? (A) Experimental; adolescents are typically in the conventional stage of moral reasoning (B) Experimental; adolescents are typically in the preconventional stage of moral reasoning (C) Longitudinal; adolescents are typically in the conventional stage of moral reasoning (D) Longitudinal; adolescents are typically in the preconventional stage of moral reasoning (E) Longitudinal; adolescents are typically in the postconventional stage of moral reasoning

Several researchers from an introductory psychology course observed infants, toddlers, and young children at a day care for one week. Over the course of the week, the researchers observed the gross and fine motor skills of all the children. After reviewing the data, the researchers were able to conclude that (A) infants gain control of their arm muscles before they gain control of their neck muscles (B) young children master fine motor skills more quickly than gross motor skills (C) young children master gross motor skills more quickly than fine motor skills (D) infants master using their fingers more quickly than their torso (E) infants master controlling their feet more quickly than lifting their head

scientist determined the rate of an enzyme-catalyzed reaction by measuring the amount of product formed over time. The following curve was generated from the data collected. What is the most likely explanation for the change in the slope of the line between 3 and 5 minutes? A The enzyme had denatured. B The enzyme had achieved its maximum velocity. C A large amount of the substrate had been consumed. D An allosteric inhibitor appeared. E There was a dramatic change in the pH.

C A large amount of the substrate had been consumed.

The graph above shows changes in glucagon and insulin secretions at different concentrations of blood glucose. Which of the following feedback mechanisms is best supported by the data? A A falling glucagon level causes a rise in the insulin level, which maintains equal amounts of both hormones in the blood. B A high glucagon level causes a rise in the insulin level, which maintains high levels of both hormones in the blood. C A low glucose level causes the release of glucagon, which stimulates the release of more glucose from tissues, which in turn lowers the amount of glucagon being released. D A low glucose level causes the release of insulin, which stimulates the release of more glucose from tissues, which in turn increases the amount of insulin being released.

C A low glucose level causes the release of glucagon, which stimulates the release of more glucose from tissues, which in turn lowers the amount of glucagon being released.

Which of the following steps in a signaling pathway typically occurs first once a chemical messenger reaches a target cell? A) Specific genes are activated. B) A second messenger molecule is produced. C) A ligand binds to a receptor. D) Specific proteins are synthesized.

C) A ligand binds to a receptor.

Directions: Each group of questions below concerns an experimental or laboratory situation or data. In each case, first study the description of the situation or data. Then choose the one best answer to each question following it. A tissue culture of vertebrate muscle was provided with a constant excess supply of glucose under anaerobic conditions starting at time zero and the amounts of pyruvic acid and ATP produced were measured. The solid line in the graph above represents the pyruvic acid produced in moles per liter per minute. ATP levels were also found to be highest at points A and C, lowest at B and D. A second culture was set up under the same conditions, except that substance X was added, and the results are indicated by the dotted line. Which of the following best accounts for the shape of the solid line between points A and D? A After ten minutes the cellular enzymes became ineffective. B Respiration became uncontrolled. C ATP acted as an allosteric inhibitor on one or more of the enzymes. D The measurements of pyruvic acid were unreliable. E The cells required more glucose than was being provided. Related Content & Skills Topic3.3 SkillSkill 4.B

C ATP acted as an allosteric inhibitor on one or more of the enzymes.

Many human cells can be stimulated to divide by hormonelike growth factors that bind to receptor proteins (R) on the plasma membrane and trigger an internal signal-transduction cascade. In many cases, however, the process of contact inhibition prevents mitosis when cells are in direct contact with one another. Contact inhibition occurs when proteins called cell adhesion molecules (CAMs) interact, causing them to change shape so that the growth-factor signaling proteins that normally associate with CAMs are replaced by another protein, called M. Both pathways are depicted in the figures below. Which of the following statements accurately uses the information presented to support the hypothesis that interruption of M function in a single body cell can result in cancer? A Protein 3 will be prevented from interacting with CAMs, causing the cell cycle to stop permanently. B The ras protein will remain bound to DNA, blocking expression of genes required for mitosis. C Growth-factor signaling can trigger mitosis in cells that are in direct contact with other cells. D The receptor proteins of body cells will no longer bind to growth-factor proteins.

C Growth-factor signaling can trigger mitosis in cells that are in direct contact with other cells.

In response to elevated blood glucose levels, beta (β) cells in the pancreas release insulin, a regulatory hormone. Insulin signals body cells to take up glucose from the blood, which returns blood glucose levels back to normal. Type 1 diabetes is an autoimmune disorder that destroys β-cells, resulting in elevated blood glucose levels. Researchers have proposed that diabetes could be treated by implanting human embryonic stem cells (hESCs) that have been induced to develop into β-cells (hESC-β). To test the proposed treatment, the researchers set up two groups of genetically identical mice and implanted the mice from one group with hESC-β cells. Several weeks after the hESC-β implant, both groups of mice were given a drug (STZ) that selectively destroys the naturally occurring mouse β-cells but does not affect the implanted hESC-β cells. Figure 1 shows a comparison of average blood glucose levels in both groups of mice. A Decreased insulin secretion by body cells → increased glucose uptake by mouse β-cells → increased insulin secretion by body cells B Increased insulin production by mouse β-cells → increased glucose uptake by hESC-β cells → decreased glucose metabolism by body cells C Increased insulin secretion by hESC-β cells → increased glucose uptake by body cells → decreased insulin secretion by hESC-β cells D Increased metabolism of glucose by hESC-β cells → differentiation of hESC-β cell into body cells → increased glucose production by body cells

C Increased insulin secretion by hESC-β cells → increased glucose uptake by body cells → decreased insulin secretion by hESC-β cells

The Hedgehog protein (Hh) plays a critical role during a certain period of embryo development, but it normally has no role in adults except for the maintenance of adult stem cells. However, the Hedgehog protein has been detected in 70 percent of pancreatic cancer cell samples. As illustrated in the figures below, the Hedgehog protein binds to an integral membrane protein receptor known as Patched (Ptc), thus initiating a pathway of gene expression. When Hedgehog is absent, Ptc inhibits another protein known as Smoothened (Smo), which, in turn, blocks the activation of a group of proteins collectively known as the Hedgehog signaling complex (HSC). The inactivation is the result of proteolytic cleavage of one component of the HSC complex, a transcription factor known as Cubitus interruptus (Ci). When Hedgehog is present, it binds to Ptc, which prevents the inhibition of Smo by Ptc. The result is that Ci remains intact and can enter the nucleus, where it binds to and activates certain genes. A Treating patients with a molecule that is structurally similar to Hedgehog and that will bind to and interact with Ptc in the same fashion as Hedgehog B Injecting patients with embryonic cells so that Hedgehog will bind to those cells instead of the cancer cells C Treating patients with a membrane-soluble compound that can bind to Smo and block its activity D Injecting patients with a preparation of purified membrane-soluble Ci that will enter the nuclei of the cancer cells and induce gene transcription

C Treating patients with a membrane-soluble compound that can bind to Smo and block its activity

If chemical signals in the cytoplasm control the progression of a cell to the M phase of the cell cycle, then fusion of a cell in G1 with a cell in early M phase would most likely result in the A replication of chromosomes only in the G1 cell B exiting of both cells from the cell cycle and into the G0 phase C condensation of chromatin in preparation of nuclear division in both cells D transfer of organelles from the G1 cell to the cell in the M phase

C condensation of chromatin in preparation of nuclear division in both cells

Directions: Each group of questions below concerns an experimental or laboratory situation or data. In each case, first study the description of the situation or data. Then choose the one best answer to each question following it. The following questions refer to the following information and graph. The data presented in the figure below are measurements of the rate of oxygen consumption at differing body masses in a species of fish. Each point represents measurements from a different fish. Measurements were taken at different temperatures. (○= 10°C,●= 15°C, □= 20°C, ■= 25°C.) The fact that each line on the graph rises from left to right means that A higher temperatures produce higher rates of metabolism B there were more large fish in the samples taken at high temperatures C larger fish consume more oxygen than smaller fish at all four temperatures D when measurements are taken for larger fish late in the day, observed values are higher E larger fish prefer to live at higher temperatures than do smaller fish

C larger fish consume more oxygen than smaller fish at all four temperatures

A student placed 20 tobacco seeds of the same species on moist paper towels in each of two petri dishes. Dish A was wrapped completely in an opaque cover to exclude all light. Dish B was not wrapped. The dishes were placed equidistant from a light source set to a cycle of 14 hours of light and 10 hours of dark. All other conditions were the same for both dishes. The dishes were examined after 7 days, and the opaque cover was permanently removed from dish A. Both dishes were returned to the light and examined again at 14 days. The following data were obtained. Additional observations were made on day 21, and no yellow-leaved seedlings were found alive in either dish. This is most likely because A yellow-leaved seedlings were unable to absorb water from the paper towels B taller green-leaved seedlings blocked the light and prevented photosynthesis C yellow-leaved seedlings were unable to convert light energy to chemical energy D a higher rate of respiration in yellow-leaved seedlings depleted their stored nutrients Related Content & Skills

C yellow-leaved seedlings were unable to convert light energy to chemical energy

Students in a class were divided into five groups to analyze community structure. Each group of students assessed the species of plants in four environments and determined the Simpson's Diversity Index for each environment. The Simpson's Diversity Index takes into account the number of species present as well as the abundance of each species. The index values are shown in Figure 1. Figure 1. Simpson's Diversity Index for four environments Based on the data in Figure 1, which of the following statements is most accurate about the species diversity of the four different environments that the students analyzed?

C = Based on the data, there is no statistically significant difference between the species diversity of plants in the light, moist environment and in the dark, moist environment: Because the error bars overlap, the light, moist and dark, moist environments show no significant statistical difference in diversity.

A study recorded changes in the distribution of some commercial marine species off the East Coast of the United States over a period of several decades. The results of the study are summarized in Figure 1. Figure 1. Latitude that is the center of commercial harvesting of specified marine species Some researchers link changes in the distribution of these species to warming of the oceans due to climate change. Which of the following pieces of data best supports this alternative hypothesis?

C = The prey of these species require colder waters to survive, and owing to warming in the oceans, they are moving farther north, to higher latitudes, where the water is colder: Global increases in average temperature are associated with global climate change. This would produce warming in the oceans, so the prey these fish depend on can survive only by moving to more northern latitudes with colder waters. The fish would move with their food sources.

A student used microscopy to investigate the relative lengths of the different stages of mitosis. The student prepared slides of cells isolated from a growing onion root tip and viewed the slides under a dissecting microscope. The student then made diagrams of cells that were in different stages of mitosis and counted the number of cells that were in each of those stages. The student's data are presented in Table 1. Table 1. Number of cells in each of four different stages of mitosis: Metaphase: 7 Telophase: 4 Prophase: 25 Anaphase: 2 Based on the data, the percent of the mitotic cells that were in metaphase is closest to which of the following? A) 5% B) 11% C) 18% D) 66%

C) 18%

A model of the typical life cycle of a cell is shown in Figure 1. Scientists have estimated that it takes yeast cells approximately 20 hours to complete the entire cycle. Table 1 shows the amount of time in each phase of the life cycle for yeast cells. Table 1. Amount of time spent in each stage of the cell cycle by yeast cells: Stage M G1 S G2 Time (hours) 2 10 5 3 Based on Table 1, what percent of the life cycle of yeast cells is spent in DNA replication? A) 5 percent B) 10 percent C) 25 percent D) 50 percent

C) 25 percent

C) A ligand binds to a receptor.

Which of the following (based on Figure 1-2 and Table 1-1) best describes the process that adds a monosaccharide to an existing polysaccharide? A) The monosaccharide is completely broken down by a specific enzyme and then atoms are reorganized and made into a polysaccharide. B) Ionic Bonds are formed between adjacent carbon atoms of the monosaccharide and the polysaccharide by adding water (H2O) and a specific enzyme. C) A specific enzyme removes the hydrogen (H) from the monosaccharide and the hydroxide (OH) from the polysaccharide, creating a bond between the two and creating a water (H2O) molecule. D) A specific enzyme removes two hydroxides (OH), one from the monosaccharide, and one from the polysaccharide, creating a bond between the two monosaccharides and creating a hydrogen peroxide (H2O2) molecule.

C) A specific enzyme removes the hydrogen (H) from the monosaccharide and the hydroxide (OH) from the polysaccharide, creating a bond between the two and creating a water (H2O) molecule.

Based on Table 5-9, which of the following is most likely the immediate cause of the first appearance of Huntington's disease in a person? A) A point mutation occurs in the HTT gene B) The first appearance of CAG repeat occurs in the HTT gene. C) An allele with more than 39 CAG repeats was inherited by the affected person. D) The person inherited two alleles that each contained 20 CAG repeats.

C) An allele with more than 39 CAG repeats was inherited by the affected person.

Cells from an advanced malignant tumor most often have very abnormal chromosomes, and often an abnormal total number of chromosomes. Why might this occur?

C) Chromosomally abnormal cells can still go through cell cycle checkpoints.

Which of the following is true of a species that has a chromosome number of 2n = 16?

C) Each cell has 8 homologous pairs.

Aminolevulinate dehydratase (ALAD) is an enzyme that relies on zinc as a coenzyme. A zinc ion binds to the ALAD active site, where it forms favorable interactions with the side chains of three amino acids. Researchers have found that substituting a lead ion for a zinc ion in the ALAD active site causes inhibition of ALAD. Which of the following statements best helps explain how the lead ion causes inhibition of ALAD? A) It changes the shape and charge of the substrate so that it becomes more compatible with ALAD's active site B) It changes the amino acid sequence of the ALAD protein so that the enzyme catalyze a different reaction. C) It changes the three-dimensional structure of the active site so that ALAD is no longer compatible with its substrate. D) It changes the enzyme-substrate complex so that the transition state is more stable and the reaction proceeds at a faster rate.

C) It changes the three-dimensional structure of the active site so that ALAD is no longer compatible with its substrate.

Which of the following best explains how the sweet pea plants in the parental generation produce F1 offspring with 14 chromosomes based on Figure 5-1 and Table 5-1? A) Meiosis II and IIII lead to the formation of cells with 14 chromosomes. When two cells combine during fertilization, extra chromosomes are randomly broken down, leading to offspring with 14 chromosomes. B) Meiosis I and II lead to the formation of cells with 14 chromosomes. When two cells combine during fertilization, extra chromosomes with recessive traits are broken down, leading to offspring with 14 chromosomes. C) Meiosis I and II lead to the formation of cells with 7 chromosomes. During meiosis I, homologous chromosomes separate. During meiosis II, sister chromatids separate. Two cells combine during fertilization to produce offspring with 14 chromosomes. D) Meiosis I and II lead to the formation of cells with 7 chromosomes. During meiosis I, sister chromatids separate. During meiosis II, homologous chromosomes separate. Two cells combine during fertilization to produce offspring with 14 chromosomes.

C) Meiosis I and II lead to the formation of cells with 7 chromosomes. During meiosis I, homologous chromosomes separate. During meiosis II, sister chromatids separate. Two cells combine during fertilization to produce offspring with 14 chromosomes.

Which of the following describes a key difference among the 20 amino acids that are used to make proteins? A) Only some amino acids have an R-Group. B) Only some amino acids have a carboxyl group. C) Only some amino acids are hydrophobic. D) Some amino acids contain the element phosphorus.

C) Only some amino acids are hydrophobic.

For sexually reproducing diploid parent cells, which of the following statements best explains the production of haploid cells that occurs in meiosis but not in mitosis? A) Separation of chromatids occurs once, and there is one round of cell division in meiosis. B) Separation of chromatids occurs twice, and there are two rounds of cell division in mitosis. C) Separation of chromatids occurs once, and there are two rounds of cell division in meiosis. D) Separation of chromatids occurs twice, and there is one round of cell division in mitosis.

C) Separation of chromatids occurs once, and there are two rounds of cell division in meiosis.

Which test tubes are controls in the experiment based on Table 3-1? A) Test tubes 1 and 2 only B) Test tubes 5 and 6 only C) Test tubes 1, 3, 5, and 7 D) Test tubes 2, 4, 6, and 8

C) Test tubes 1, 3, 5, and 7

Which of the following best predicts the immediate result of adding more substrate to the reaction mixture at the point indicated by the arrow in Figure 3-3? A) The amount of product will increase until the reaction rate goes to zero. B) The amount of product will decrease until the reaction reaches its equilibrium point or the enzyme has been used up by the reaction. C) The amount of product will increase until the reaction reaches its equilibrium point or until the substrate is used up by the reaction. D) The amount of product will increase without stopping because the enzyme will be unchanged by the reaction.

C) The amount of product will increase until the reaction reaches its equilibrium point or until the substrate is used up by the reaction.

One of the researchers proposes using oxygen gas production to measure reaction rates. Which of the following statements best justifies the use of the proposed modification as a way of creating an appropriate control for the investigation based on Figure 3-1? A) The experiment can be repeated without hydrogen peroxide, which will help eliminate an uncontrolled variable. B) The experiment can be repeated without peroxidase, which will introduce a second independent variable. C) The experiment can be repeated without guaiacol, which will reveal the effect of guaiacol on the reaction rates. D) The experiment can be repeated without water, which will reveal whether the reaction can occur inside a living cell.

C) The experiment can be repeated without guaiacol, which will reveal the effect of guaiacol on the reaction rates.

A hydrophilic peptide hormone is produced in the anterior pituitary gland located at the base of the brain. The hormone targets specific cells in many parts of the body. Which of the following best explains a possible mechanism that would enable the hormone to efficiently reach all of the target cells in the body? A) The hormone interacts with the nerves at the base of the brain and directs signals to the target cells through the nervous system. B) The hormone diffuses into target cells adjacent to the anterior pituitary gland, where the hormone is degraded. C) The hormone is released into the bloodstream where it can be transported to all cells with the correct receptors. D) The hormone moves through cytoplasmic connections between cells until it has reached all cells with the correct intracellular binding sites.

C) The hormone is released into the bloodstream where it can be transported to all cells with the correct receptors.

Based on Figure 1-5 which of the following is the most likely reason for the difference in leaf growth? A) The phosphorus-starved plant was unable to synthesize both the required proteins and lipids, limiting growth. B) The phosphorus-starved plant was unable to synthesize both the required proteins and carbohydrates, limiting growth. C) The phosphorus-starved plant was unable to synthesize both the required nucleic acids and lipids, limiting growth. D) The phosphorus-starved plant was unable to synthesize both the required carbohydrates and nucleic acids, limiting growth.

C) The phosphorus-starved plant was unable to synthesize both the required nucleic acids and lipids, limiting growth.

Based on diagram 1-1, which of the following best describes how the structure of ice benefits the organisms that live in the water below? A) The water molecules in ice are closer together than those in liquid water, so the ice prevents the passage of air to the water, maintaining a constant gas mixture in the water. B) The water molecules in ice are closer together than those in liquid water, so the ice forms a barrier that protects the organisms in the water from the freezing air temperatures. C) The water molecules in ice are farther apart than those in liquid water, so the ice floats, maintaining the warmer, denser water at the lake bottom. D) The water molecules in ice are farther apart than those in liquid water, so the ice floats, preventing the escape of gases from the liquid water.

C) The water molecules in ice are farther apart than those in liquid water, so the ice floats, maintaining the warmer, denser water at the lake bottom.

Which of the following statements is consistent with the data in Figure 4-10? A) The cells have a haploid chromosome number of 3. B) The cells have a diploid chromosome number of 6. C) There is a change from 3 to 6 picograms of DNA because DNA is replicated before each round of cell division. D) There is a change from 6 to 3 picograms of DNA after each cell division because the chromosomes lengthen following cell division.

C) There is a change from 3 to 6 picograms of DNA because DNA is replicated before each round of cell division

Researchers tracked the amount of DNA (measured in picograms) over time beginning with a single cell and continuing through several rounds of cell division. The researchers observed threadlike chromosomes prior to cell division. The threadlike chromosomes disappeared from view shortly after each division. The amount of DNA in picograms per cell over several rounds of cell division is shown in Figure 1. Which of the following statements is consistent with the data in Figure 1? A) The cells have a haploid chromosome number of 3. B) The cells have a diploid chromosome number of 6. C) There is a change from 3 to 6 picograms of DNA because DNA is replicated before each round of cell division. D) There is a change from 6 to 3 picograms of DNA after each cell division because the chromosomes lengthen following cell division.

C) There is a change from 3 to 6 picograms of DNA because DNA is replicated before each round of cell division.

The tumor suppressor protein p53 binds to DNA and activates target genes, which results in the synthesis of p21, CD95, and other proteins. The p21 protein promotes cell-cycle arrest, whereas the CD95 protein promotes apoptosis. Which of the following will most likely result from a loss of p53 function? A) Rapid cell growth without cell division B) Immediate activation of apoptosis pathways C) Uncontrolled cell proliferation D) Increased expression of p53 target genes

C) Uncontrolled cell proliferation

A researcher claims that budding yeast are able to survive in different environments because they produce enzymes that allow them to use different molecules as sources of matter and energy. Which of the following statements best helps justify the researcher's claim by providing a relevant example? A) Yeast cells produce protein kinases, which are enzymes that catalyze the transfer of phosphate groups from ATP to protein substrates. B) Yeast cells produce DNA polymerases, which are enzymes that catalyze the conversion of free nucleotides into strands of DNA. C) Yeast cells produce invertase, which is an enzyme that catalyzes the conversion of the disaccharide sucrose into glucose and fructose. D) Yeast cells produce catalase, which is an enzyme that catalyzes the conversion of hydrogen peroxide into water and oxygen gas.

C) Yeast cells produce invertase, which is an enzyme that catalyzes the conversion of the disaccharide sucrose into glucose and fructose.

As an embryo develops, new cells are produced as the result of

C) cell division

From earliest to latest, the overall sequence of early development proceeds as follows:

C) cleavage → gastrulation → organogenesis

The outer-to-inner sequence of tissue layers in a post-gastrulation vertebrate embryo is

C) ectoderm → mesoderm → endoderm.

Besides the ability of some cancer cells to overproliferate, what else could logically result in a tumor?

C) lack of appropriate cell death

Chromosomes first become visible during which phase of mitosis?

C) prophase

What would the population size of sika deer be one year after the carrying capacity increased to 70,000 as a result of deforestation? Assume rmax does not change.

C. The population would grow to 63,667 deer in a year, and the growth rate would decrease the following year.

Which of the following hypotheses about the effect of zebra mussels on the Hudson River community is best supported by the data in Figure 1 ?

C. The reduction in primary productivity has resulted in an unstable community that will eventually collapse.

Figure 2. Change in host preference by Culex cedecei between 1979 and 2016. Numbers do not add up to one hundred percent because these represent a subset of all the host species. Which of the following populations have significantly decreased in size between 1996 and 2011 ?

C. White-tailed deer and raccoons only

Cancer can result from a variety of different mutational events. Which of the following is LEAST likely to result in the initiation of a cancerous tumor? A. A receptor mutation results in activation of a cell-division pathway in the absence of the appropriate ligand. B. A mutation results in the loss of the ability to produce a tumor-suppressor protein. C. A defect in a cell-cycle checkpoint prevents a cell from entering the S phase. D. At the anaphase checkpoint, separation of chromatids occurs without all centromeres being attached to kinetochore microtubules from both poles.

C. A defect in a cell-cycle checkpoint prevents a cell from entering the S phase.

Different polysaccharides are used by plants for energy storage and structural support. The molecular structures for two common polysaccharides are shown in Figure 1. Starch is used by plants for energy storage, and cellulose provides structural support for cell walls. The monomer used to construct both molecules is glucose. A study determined the effect of two different digestive enzymes, A and B, on these two polysaccharides. Table 1 presents the data from the study. Mammals do not produce digestive enzyme B. However, sheep and cattle are two types of mammals that contain microorganisms in their digestive tract that produce enzyme B. Which of the following best describes the process that adds a monosaccharide to an existing polysaccharide?

C. A specific enzyme removes the hydrogen ( H ) from the monosaccharide and the hydroxide ( OH ) from the polysaccharide, creating a bond between the two and creating a water ( H2O ) molecule.

C. Bonds Y and Z at the same time

Which of the following best describes a structural similarity between the two molecules shown in Figure 1 that is relevant to their function?

C. Both molecules contain nucleotides that form base pairs with other nucleotides, which allows each molecule to act as a template in the synthesis of other nucleic acid molecules.

Cell communication is critical for the function of both unicellular and multicellular eukaryotes. Which of the following is likely true of cell signaling? A. Cell signaling uses the highest molecular weight molecules found in living cells. B. Cell signaling has largely been replaced by other cell functions in higher mammals. C. Similar cell signaling pathways in diverse eukaryotes are evidence of conserved evolutionary processes. D. Cell signaling functions mainly during early developmental stages.

C. Similar cell signaling pathways in diverse eukaryotes are evidence of conserved evolutionary processes.

The figure shows the results of an experiment to investigate the effects of an enriched CO2 environment on plant growth. Identical plants were separated into different groups and grown either in a standard CO2 environment (400 ppm CO2) or in an enriched CO2 environment (700 ppm CO2). Of the plants in each environment, half were grown under ideal conditions and half were grown under stressed conditions. Based on the figure, which statement best describes the observed relationship between atmospheric CO2 enrichment and plant growth under ideal and stressed conditions?

C. The increase in atmospheric CO2 resulted in a greater increase in plant growth under stressed conditions than under ideal conditions.

Phosphorous (P) is an important nutrient for plant growth. Figure 1 shows Arabidopsis thaliana plants grown under phosphorus‐sufficient (left) and phosphorus‐starved (right) conditions for six weeks. Which of the following is the most likely reason for the difference in leaf growth?

C. The phosphorus-starved plant was unable to synthesize both the required nucleic acids and lipids, limiting growth.

As shown in the diagram, when environmental temperatures drop below freezing, a layer of ice typically forms on the surface of bodies of freshwater such as lakes and rivers. Which of the following best describes how the structure of ice benefits the organisms that live in the water below?

C. The water molecules in ice are farther apart than those in liquid water, so the ice floats, maintaining the warmer, denser water at the lake bottom.

The cell membrane is selectively permeable due to its structure. Thus, the internal environment of the cell is distinct from the external environment of the cell. One biologist hypothesizes that small nonpolar molecules readily pass through the membrane. Another biologist alternatively hypothesizes that these types of molecules require channel and transport proteins that are embedded in the membrane in order to move across the membrane. Which of the following data would best refute this alternative hypothesis?

CO2 and N2 movement in and out of cells is unaffected when membrane protein activity is blocked.

CO2CO2 and N2N2 movement in and out of cells is unaffected when membrane protein activity is blocked.

Which of the following would most likely occur if cattle lost the ability to maintain a colony of microorganisms in their digestive tract?

Cattle would no longer be able to use cellulose as a primary source of glucose. -Without the enzyme B produced by microorganisms in their digestive tract, cellulose would pass through the digestive tract without being digested.

Based on the data, which cell is likely to be most effective in the exchange of materials?

Cell 2

What changes the rate of cell division

Cell crowding

In what way do the membranes of a eukaryotic cell vary?

Certain proteins are unique to each kind of membrane.

Which of the following best describes the role of cell to cell communication during a response to an invasion of antigens?

Chemicals that are secreted from antigen-presenting cells then activate helper T cells.

Researchers have proposed a model of chloroplast evolution. According to the model, chloroplasts evolved from a small prokaryotic organism that was engulfed by an ancestral eukaryote. The engulfed prokaryote then formed an endosymbiotic relationship with the eukaryotic host. Which of the following observations best supports the model?

Chloroplasts and some prokaryotes share similar photosynthetic reactions.

The engulfed prokaryote then formed an Endosymbiotic relationship with the eukaryotic host. Which of the following observations best supports the model?

Chloroplasts and some prokaryotes share similar photosynthetic reactions.

To apply parsimony to constructing a phylogenetic tree...

Choose the tree that represents the fewest evolutionary changes, either in DNA sequences or morphology

Translocation

Chromosome abnormality caused by rearrangement of parts between nonhomologous chromosomes

Of the following, which is the best next step for the researchers to best determine the long-term effectiveness of these insecticides with regards to the development of resistance?

Continue treating the three insect populations with the same insecticides and determine whether their efficiencies decline significantly after several generations.

Human activities can drive changes in ecosystems that affect the risk of extinction. An experiment is designed to help prevent the further decline and extinction of the Henslow's sparrow in which controlled burns will be set in the each of the ten Midwest counties in order to prevent the regrowth of the forest. Which of the following represents an alternate hypothesis tested by this experiment with regard to the population sizes of Henslow's sparrows?

Controlled fires in counties 4 and 5 will lead to an increase in the sparrow population.

Transgenic animals are becoming more important to our food supply. Examples of genetically modified animals include all of the following except A. lactating goats injected with spider genes that produce silk along with their milk. B. genetically modified pigs that produce more lean meat. C. transgenic salmon placed into aquaculture facilities with wild salmon. D. cows injected with hormones to increase milk production.

Cows injected with hormones to increase milk production.

47) Researchers tried to explain how vesicular transport occurs in cells by attempting to assemble the transport components. They set up microtubular tracks along which vesicles could be transported, and they added vesicles and ATP (because they knew the transport process requires energy). Yet, when they put everything together, there was no movement or transport of vesicles. What were they missing? A) an axon B) contractile microfilaments C) endoplasmic reticulum D) motor proteins

The molecular formula for glucose is C₆H₁₂O₆. What would be the molecular formula for a polymer made by the lining 10 glucose molecules together by dehydration reactions?

C₆₀H₁₀₂O₅₁

25) The Golgi apparatus has a polarity, or sidedness, to its structure and function. Which of the following statements correctly describes this polarity? A) Transport vesicles fuse with one side of the Golgi and leave from the opposite side. B) Proteins in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. C) Lipids in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. D) All of the listed responses correctly describe polarity characteristics of the Golgi function.

27. Which of the following is not heavily influenced by environmental influences? a. Continuous Generations b. Discontinuous Generations c. Continuous Variation d. Discontinuous Variation e. None of the above

32) Asbestos is a material that was once used extensively in construction. One risk from working in a building that contains asbestos is the development of asbestosis caused by the inhalation of asbestos fibers. Cells will phagocytize asbestos, but are not able to degrade it. As a result, asbestos fibers accumulate in _____. A) mitochondria B) ribosomes C) peroxisomes D) lysosomes

48) Cilia and flagella bend because of _____. A) conformational changes in ATP that thrust microtubules laterally B) a motor protein called radial spokes C) the quick inward movements of water by osmosis. D) a motor protein called dynein

5. Gregor Mendel studied genetics with what type of plant? a. Pumpkin b. Potato c. Tomato d. Pea e. Bean

50) Cytochalasin D is a drug that prevents actin polymerization. A cell treated with cytochalasin D will still be able to _____. A) divide in two B) contract muscle fibers C) extend pseudopodia D) move vesicles within a cell

55) The extracellular matrix is thought to participate in the regulation of animal cell behavior by communicating information from the outside to the inside of the cell via which of the following? A) gap junctions B) the nucleus C) DNA and RNA D) integrins

57) Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through _____. A) plasmodesmata B) tight junctions C) desmosomes D) gap junctions

7) All of the following are part of a prokaryotic cell EXCEPT _____. A) a cell wall B) a plasma membrane C) ribosomes D) an endoplasmic reticulum

Water molecules are polar covalent molecules. There is a partial negative charge near the oxygen atom and partial positive charges near the hydrogen atoms due to the uneven distribution of electrons between the atoms, which results in the formation of hydrogen bonds between water molecules. The polarity of water molecules contributes to many properties of water that are important for biological processes. Which of the following models best demonstrates the arrangement of hydrogen bonds between adjacent water molecules?

Which of the following models shows how cholesterol molecules most likely interact with the phospholipid bilayer of a cell's plasma membrane?

Which of the following results, one hour after membrane fusion, best supports the alternative hypothesis that the cell membrane is a fluid mosaic?

The diagram above illustrates feedback control as exerted by the hormone thyroxine. Following surgical removal of the thyroid gland, the level of TSH in the blood will increase. Which of the following best explains this increase? A Residual blood thyroxine, from prior to thyroid gland removal, will bind to cells in the anterior pituitary, signaling more TSH secretion. B Thyroxine will remain bound to thyroxine receptors on various body cells, and these body cells will secrete additional hormones that stimulate the anterior pituitary to secrete TSH. C Thyroxine that was stored in the anterior pituitary prior to thyroid gland removal will signal more TSH secretion. D A decrease in thyroxine levels means a loss of inhibition to the hypothalamus and anterior pituitary, leading to increased TSH secretion.

D A decrease in thyroxine levels means a loss of inhibition to the hypothalamus and anterior pituitary, leading to increased TSH secretion.

Cortisol is a hormone produced in response to stress, including starvation, in humans. Which of the following is most likely an immediate effect of a starvation-induced increase in cortisol secretion? A Increased activation of the immune system B Increased urine production by the kidneys C Increased bone and collagen formation D Increased mobilization of fatty acids from fat cells

D Increased mobilization of fatty acids from fat cells

For following group of questions first study the description of the situation and diagrams and then choose the one best answer to each question following it and fill in the corresponding oval on the answer sheet. A student studied the effects of light intensity on oxygen production in green algae. The algae were suspended in water inside a sealed glass jar, and the jar was placed into a constant-temperature, lightproof box containing a light source. A probe was inserted into the jar to record the concentration of oxygen. The probe was connected to a recording device. The setup is shown below. The student decreased the intensity of the light hourly and recorded the corresponding changes in oxygen concentration. The graph below shows the results from the recording device. The rate of oxygen production equaled the rate of oxygen consumption during which of the following time periods? A G to H B H to I C I to J D J to K E G to K

D J to K

What most likely causes the trends in oxygen concentration shown in the graph above? A The water becomes colder at night and thus holds more oxygen. B Respiration in most organisms increases at night. C More organisms are respiring at night than during the day. D Photosynthesis produces more oxygen than is consumed by respiration during the day.

D Photosynthesis produces more oxygen than is consumed by respiration during the day.

Steroid hormones, such as testosterone, pass through the plasma membrane and bind to an intracellular protein, as shown in the diagram below. The hormone-receptor complex then enters the nucleus, where it interacts with DNA to promote transcription of a specific gene. A Histone protein synthesis will increase because histones maintain the DNA in an optimal conformation for chromosome assembly. B Ribosome production will increase because ribosomes are specific for the mRNA with which they bind during translation. C DNA replication will increase as a result of the binding of the hormone-receptor complex to the DNA. D Production of a specific mRNA will increase as a result of the binding of the hormone-receptor complex to the DNA.

D Production of a specific mRNA will increase as a result of the binding of the hormone-receptor complex to the DNA.

A polypeptide is polymer of amino acids held together by peptide bonds. The process of dehydration synthesis creates these peptide bonds, as shown in Figure 1. As shown in Figure 1, an amino acid must have which of the following properties in order to be incorporated into a polypeptide?

D The ability to form a covalent bond with both its NH2 group and its COOH group.

Based on the model of eukaryotic cell cycle regulation shown in the figure, which of the following best describes the effect of a drug that blocks the production of the mitotic cyclin? A The cell cycle would proceed uncontrollably, and the cell would become cancerous. B The G1 cyclin would functionally replace mitotic cyclin, and the cell would continue dividing normally. C DNA synthesis would be prevented, and the cell would stop dividing. D The cell would be prevented from entering mitosis, and the cell would stop dividing.

D The cell would be prevented from entering mitosis, and the cell would stop dividing.

For following group of questions first study the description of the data and then choose the one best answer to each question following it and fill in the corresponding oval on the answer sheet. To study the actions of the enzyme catalase on hydrogen peroxide, students performed the following experiment. Catalase was extracted from potatoes by blending raw potatoes in a blender with cold distilled water. The filtrate was stored on ice. The following hydrogen peroxide solutions were made: 1 percent, 5 percent, 10 percent, and 15 percent. Filter paper disks were soaked in the catalase filtrate and dropped into beakers containing the various solutions. The activity of the enzyme was measured by the amount of time it took for the disks to float to the surface of the solution on the bubbles produced by the reaction. The following data were obtained. Which of the following best describes why the disks rose to the surface faster in the more concentrated hydrogen peroxide solutions? A There was more enzyme present in the more concentrated solutions. B A greater amount of heat was generated in the more concentrated solutions. C The more concentrated solutions lowered the activation energy of the reaction. D The higher substrate concentrations in the more concentrated solutions speeded the reaction. E The density of the water was lower in the more concentrated solutions.

D The higher substrate concentrations in the more concentrated solutions speeded the reaction.

Two types of cholesterol transport proteins, low-density lipoproteins (LDL) and high-density lipoproteins (HDL), bind to cholesterol and carry it through the bloodstream. Familial hypercholesterolemia (FH) is characterized by high cholesterol levels in the blood, which can lead to cardiovascular disease. FH is associated with a loss-of-function mutation of a gene that encodes LDL receptors in liver cells. Individuals who are heterozygous produce lower-than-normal amounts of the LDL receptors, and individuals who are homozygous for the mutant allele have no LDL receptor function. Individuals with FH can be treated with drugs that result in increased production of LDL receptors in liver cells. Which of the following best explains the observation that the drugs can effectively control blood cholesterol levels in individuals who are heterozygous but are not effective in individuals homozygous for the mutant allele? A The drugs repair the mutant allele by copying the wild-type allele. B The drugs prevent cholesterol from entering the liver cells in individuals who are heterozygous but not in individuals who are homozygous for the mutant allele. C Cholesterol molecules primarily bind to HDL receptors in individuals with FH. D There must be at least one copy of the wild-type LDL receptor allele to produce functional LDL receptors.

D There must be at least one copy of the wild-type LDL receptor allele to produce functional LDL receptors.

Precise regulation of specific hormone levels is required for optimal sperm production in mammals, as summarized in the figure above. Anabolic-androgenic steroids (AAS) are synthetic variants of testosterone that are sometimes abused by persons who desire to enhance their athletic performance or alter their physique. Assuming that AAS function in the same way as naturally occurring testosterone, it is most likely that long-term abuse of AAS would A stimulate FSH secretion B stimulate testosterone production C stimulate LH secretion D reduce sperm production

D reduce sperm production

Which of the following results, One hour after membrane fusion, best supports the alternative hypothesis that the cell membrane is a fluid mosaic?

D) Dark and light r mixed together

In a study of energy flow, the following data were collected: Each human requires 55 grams of protein per day. An acre of soybeans produces 200,000 grams of protein per year. A cow grazing on one acre of land produces 19,000 grams of protein per year. Based on these data, an acre of land would support: 10 humans per year on a diet of soy, or 0.9 human per year on a diet of beef. Which of the following statements best explains these relationships in terms of energy transfer?

D = Only 10% of the energy on each level of the trophic pyramid is available for use by the next level. The rest is lost as heat or used for growth and repair: The 10% rule states that approximately 90% of the energy at any trophic level is lost to heat, growth, and repair of the organisms, and only 10% is available for harvesting by the next trophic level.

A biologist was investigating the effects of herbivory on the amount of nicotine produced by the leaves of tobacco plants (Nicotiana rustica). Six groups of plants were grown from seed in the same greenhouse with identical environmental conditions. Three groups were then each exposed for a different interval of time to tobacco hornworms (Maduca sexta), which feed on the foliage of tobacco plants. The amount of nicotine present in the leaves was measured at the beginning and end of each time interval. As a control, the other three groups were not exposed to hornworms. The results of the experiment are summarized in Table 1. Which of the following correctly identifies the dependent variable and the independent variable for the experiment?

D = The dependent variable is the percent change in the amount of nicotine, and the independent variable is the time interval the plants were exposed to the hornworms: The change in the concentration of nicotine is the factor being studied and is therefore the dependent variable. The time interval the plants were exposed to the hornworms is changed by the biologist and therefore the independent variable.

Sea otters living along the Pacific coast were hunted to near extinction in the nineteenth century. After being protected from hunting in the early 1900s, a remnant population of otters near Adak Island, Alaska, recovered rapidly. Otters did not return to the environmentally similar nearby island, Alaid Island. Sea otters eat sea urchins, which eat kelp, a brown alga. Researchers surveyed both islands in 1988, to measure sea urchin biomass and kelp density. The data are presented in Table 1. In 1991, researchers at Adak Island observed the first attack by a killer whale on a sea otter in historical times. The researchers hypothesized that the population sizes of the larger marine mammals that the killer whales normally prey on declined, so the killer whales were starting to prey on different prey, including the smaller sea otters. Which of the following best predicts the effects of an increase in killer whale predation on sea otters on the Adak Island ecosystem?

D = The sea urchin population will increase and the kelp population will decrease, leading to reduced total biomass and diversity in the Adak Island ecosystem: Increased predation by killer whales will lead to a decrease in the sea otter population at Adak Island. A decline in the sea otter population will allow the sea urchin population to increase without predation as a limiting factor. An increasing sea urchin population will lead to overgrazing and reduced kelp densities. Kelp forests provide important habitat and food for many other organisms, and their decline would cause the entire ecosystem to decline. Due to this cascade effect, sea otters are described as a keystone species because when they are removed from an ecosystem, the ecosystem declines rapidly.

Which feature of model 1 best illustrates how biological information is coded in a DNA molecule? A) The 5' and 3' labels at the end of each strand B) The labeling of the hydrogen bonds between base pairs C) The lines connecting sugars and phosphate groups that represent covalent bonds D) The linear sequence of the base pairs

D) The linear sequence of the base pairs

Baker's yeast, Saccharomycetes cerevisiae, is the species of yeast that is commonly used in baking, brewing, and making wine. It is a single-celled organism; each cell is capable of undergoing asexual reproduction by mitosis and sexual reproduction by meiosis, forming spores that combine with other spores. To find out if energy and nutritional resource availability determines which form of reproduction is used, researchers grew twenty yeast colonies on an agar medium plate providing ideal nutrient environments. Each colony was composed of a population of yeast that originated from a single yeast cell that had reproduced asexually to form a population of millions of yeast clones. That plate was used to produce replicate plates of yeast colonies. Each replicate plate was a mirror image of the original cultures, so each colony could be subjected to each treatment group. The replicate plates contained different media as follows. Robust media: Contains all nutrients required by yeast in excess amounts Complete media: Contains all nutrients at a level promoting exponential growth at rmax Minimal media: Nutrients available at a low level, allowing growth, but stressing the yeast colonies Deficient media: Nutrient content less than what is needed to sustain growth, extreme stress on yeast colonies Eight replica plates were made, two plates of each media, and all plates were incubated at 30°C for 24 hours. Yeast from each colony were observed through a microscope and their means of reproduction determined. Table 1 summarizes these results. Which of the following best explains the data in Table 1 ?

D = Yeast respond to nutritional stress with sexual reproduction, producing new genetic combinations, or dormancy: Increasing stress leads to an increased number of colonies using sexual reproduction. Sexual reproduction could lead to new combinations of alleles that might allow the yeast to survive using a different energy source or produce a dormant form that could survive until the yeast cells were in a more favorable environment.

Two competing hypotheses exist regarding the cell membrane structure. One hypothesis states that membrane structure is static and membrane components throughout the bilayer are rigidly bound. Alternatively, the other hypothesis states that cell membranes are a fluid mosaic in which membrane components may drift within the bilayer around the surface of the cell. An experiment is set up in which membrane proteins of two different cells are fluorescently labeled with two different colors and then fused as shown in Figure 1. Figure 1. Model of initiation of cell fusion experiment Which of the following results, one hour after membrane fusion, best supports the alternative hypothesis that the cell membrane is a fluid mosaic?

D diffused evenly

A group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 8 picograms of DNA per nucleus. Those cells would have __________ picograms at the end of the S phase and __________ picograms at the end of G2.

D) 16; 16

Cytokinesis usually, but not always, follows mitosis. If a cell completed mitosis but not cytokinesis, the result would be a cell with

D) 2 nuclei

A researcher proposes a model to explain how enzyme-substrate interactions determine enzyme specificity. The model is based on the idea that substrate molecules form favorable interactions with the amino acid side chains in an enzyme's active site. Based on the model, which of the following statements best explains an enzyme's specificity for a particular substrate molecule? A) A hydrophilic molecule interacts with nonpolar side chains in the enzyme's active site B) A hydrophobic molecule interacts with polar side chains in the enzyme's active site. C) A molecule with positive charges interacts with positively charged side chains in the enzyme's active site. D) A molecule with negative charges interacts with positively charged side chains in the enzyme's active site.

D) A molecule with negative charges interacts with positively charged side chains in the enzyme's active site.

Which of the following (based on Figure 1-2 and Table 1-1) would be most likely to occur if cattle lost the ability to maintain a colony of microorganisms in their digestive tract? A) Cattle would no longer be able to synthesize cellulose. B) Cattle would have to convert cellulose to starch by digesting it. C) Cattle would have to start producing enzyme B without the help of the bacteria. D) Cattle would no longer be able to use cellulose as a primary source of glucose.

D) Cattle would no longer be able to use cellulose as a primary source of glucose.

Blood clots are formed by a positive feedback loop. Two pathways exist, the extrinsic and intrinsic pathways, which converge during clot formation. There are many clotting factors involved, most of which are proteins. Vitamin K is required for the formation of the active form of several of the clotting factors, including Factor X. A simplified model of the blood clotting process is shown in Figure 1. Warfarin is a drug used to treat certain blood clots. Warfarin blocks the formation of the active form of vitamin K-dependent clotting factors. Based on the model, which of the following best predicts the effects of warfarin on a patient? A) Fibrinogen will form fibrin, but the clot will not form because Factor XIII will not be synthesized. B) The intrinsic pathway will take over because the clotting factors are part of that pathway. C) Thrombin will be converted to prothrombin because Factor X will reverse the reaction. D) Factor X will not be activated, which will prevent thrombin from forming.

D) Factor X will not be activated, which will prevent thrombin from forming.

Warfarin is a drug used to treat certain blood clots. Warfarin blocks the formation of the active form of vitamin K-dependent clotting factors. Based on Figure 4-6, which of the following best predicts the effects of warfarin on a patient? A) Fibrinogen will form fibrin, but the clot will not form because Factor X will not be synthesized. B) The intrinsic pathway will take over because the clotting factors are part of that pathway. C) Thrombin will be converted to prothrombin because Factor X will reverse the reaction. D) Factor X will not be activated, which will prevent thrombin from forming.

D) Factor X will not be activated, which will prevent thrombin from forming.

Which of the following best explains a distinction between metaphase I and metaphase II? (You can use Figure 5-2 as a reference here) A) The nuclear membrane breaks down during metaphase I but not during metaphase II. B) Chromosomes align at the equator of the cell during metaphase II but not during metaphase I. C) The meiotic spindle is needed during metaphase I but not during metaphase II. D) Homologous pairs of chromosomes are aligned during metaphase I, but individual chromosomes are aligned during metaphase II.

D) Homologous pairs of chromosomes are aligned during metaphase II, but individual chromosomes are aligned during metaphase IIII.

A compound that prevents the separation of the homologous chromosomes in anaphase I is being studied. Which of the following questions can be best answered during this study based on Figure 5-3? A) Will the cells produced at the end of meiosis still be genetically identical to each other in the presence of this compound? B) Will the long-term development of the individual be affected by this meiotic error? C) When do the centrosomes start to move apart during meiosis I as compared to meiosis II? D) Is there a pattern to the movement of homologous chromosomes in the presence of this compound?

D) Is there a pattern to the movement of homologous chromosomes in the presence of this compound?

Which of the following statements is correct about the molecule shown in Figure 1-9? A) It is RNA because of the relative direction of the two strands. B) It is RNA because of the number of different nucleotides found in the molecule. C) It is DNA because of the nature of the hydrogen bonds between guanine and cytosine. D) It is DNA because of the nucleotides present.

D) It is DNA because of the nucleotides present.

Based on the sample means in Figure 4-8, which of the following conclusions about the cells in the growing root tips of Zea mays seedlings is best supported by the results of the experiment? A) The cells of the root tips grow to larger sizes when the seedlings are planted in compact sand than when the seedlings are planted in loose sand. B) The average rate of mitotic cell division is greater for the root tips growing in loose sand than for the root tips growing in compact sand. C) The average cell cycle time is greater for the root tips growing in compact sand than for the root tips growing in loose sand. D) More cells are produced per unit of time in the root tips growing in compact sand than in the root tips growing in loose sand.

D) More cells are produced per unit of time in the root tips growing in compact sand than in the root tips growing in loose sand.

Researchers grew seedlings of corn, Zea mays, in loose and compact sand. The researchers measured the amount of time required for the cells in the growing root tips of the seedlings to double in number. The mean cell doubling times for the two groups of seedlings are shown in Figure 1. Based on the sample means, which of the following conclusions about the cells in the growing root tips of Zea mays seedlings is best supported by the results of the experiment? A) The cells of the root tips grow to larger sizes when the seedlings are planted in compact sand than when the seedlings are planted in loose sand. B) The average rate of mitotic cell division is greater for the root tips growing in loose sand than for the root tips growing in compact sand. C) The average cell cycle time is greater for the root tips growing in compact sand than for the root tips growing in loose sand. D) More cells are produced per unit of time in the root tips growing in compact sand than in the root tips growing in loose sand.

D) More cells are produced per unit of time in the root tips growing in compact sand than in the root tips growing in loose sand.

Which of the following statements about genes is incorrect?

D) One gene only is used in a specific cell type.

Which of the following actions will provide a negative control for the investigation based on Figure 3-1? A) Repeating the experiment at 25°C B) Repeating the experiment using twice the amount of hydrogen peroxide C) Repeating the experiment using twice the amount of peroxidase D) Repeating the experiment using heat-denatured peroxidase

D) Repeating the experiment using heat-denatured peroxidase

Based on Figure 4-2, which of the following outcomes will most likely result from the inactivation of the beta-2 adrenergic receptor? A) The cellular concentration of cyclic AMP will increase. B) The enzymatic activity of protein kinase A will increase. C) The activation of glycogen phosphorylase will increase. D) The rate of glycogen synthesis in the cell will increase.

D) The rate of glycogen synthesis in the cell will increase.

A cell culture commonly used in research was selected to study the effect of a specific virus on the timing of cell cycle phases. Two separate cultures were started, one untreated and one inoculated with the virus. Both cultures were incubated under identical conditions. After a period of time, 200 cells from each culture were observed and classified as shown in Table 1. Table 1. Number of normal and infected cells found in three phases of the cell cycle: Phase of Cell Cycle: G0 Untreated Cells (n=200): 196 Virus-Infected Cells (n=200): 10 Phase of Cell Cycle: Interphase Untreated Cells (n=200): 2 Virus-Infected Cells (n=200): 40 Phase of Cell Cycle: Mitosis Untreated Cells (n=200): 2 Virus-Infected Cells (n=200): 150 Which of the following most accurately describes an observation and an effect of the viral infection indicated by the data in Table 1? A) Normal cells spend 98 percent of their time cycling in and out of interphase. The virus reduces this to 5 percent of the time. B) Twenty percent of the virus-infected cells are in interphase. These cells are no longer part of the cell cycle. C) Forty percent of the virus-infected cells are in interphase. These cells are preparing for replication of genetic material. D) Seventy-five percent of the virus-infected cells are found in mitosis. The virus stimulates frequent cell division.

D) Seventy-five percent of the virus-infected cells are found in mitosis. The virus stimulates frequent cell division.

Which of the following most accurately describes an observation and an effect of the viral infection indicated by the data in Table 4-2? A) Normal cells spend 98 percent of their time cycling in and out of interphase. The virus reduces this to 5 percent of the time. B) Twenty percent of the virus-infected cells are in interphase. These cells are no longer part of the cell cycle. C) Forty percent of the virus-infected cells are in interphase. These cells are preparing for replication of genetic material. D) Seventy-five percent of the virus-infected cells are found in mitosis. The virus stimulates frequent cell division.

D) Seventy-five percent of the virus-infected cells are found in mitosis. The virus stimulates frequent cell division.

A researcher claims that genetic variation provides organisms with the ability to survive and reproduce in different environments. To support the claim, the researcher makes the following observation: bacteria that contain plasmids (small DNA molecules) are resistant to a wider range of antibiotics than are bacteria that contain no plasmids. Which of the following statements best establishes a connection between the observation and the researcher's claim? A) Some antibiotics inhibit the synthesis of bacterial cell walls. B) Some antibiotics inhibit protein synthesis in bacteria cells. C) Some plasmids cannot exist in a bacterial cell with certain other plasmids. D) Some plasmids contain antibiotic resistance genes.

D) Some plasmids contain antibiotic resistance genes.

Phycobiliproteins are a complex of accessory pigments and proteins found in cyanobacteria but not in green algae. A researcher claims that the phycobiliprotein pigments in cyanobacteria allow the cyanobacteria to survive in certain aquatic niches better than green algae can. Which of the following statements best justifies the researcher's claim? A) The additional pigments allow the cyanobacteria to store light energy so that it can be used at night to continue photosynthesis. B) The additional pigments block light and prevent it from reaching photosynthetic organisms at greater depths, so no photosynthetic organisms can live below the surface waters containing cyanobacteria. C) The additional pigments require energy and cellular resources to produce, so they can be used as an energy source during times of insufficient light. D) The additional pigments absorb light at wavelengths that green algae cannot absorb; this may allow cyanobacteria to capture more light energy for photosynthesis than green algae can in certain areas.

D) The additional pigments absorb light at wavelengths that green algae cannot absorb; this may allow cyanobacteria to capture more light energy for photosynthesis than green algae can in certain areas.

Using a significance level of p=0.05, which of the following statements best completes a chi-square goodness-of-fit test for a model of independent assortment based on Table 5-3? A) The calculated chi-square value is 0.66, and the critical value is 0.05. The null hypothesis can be rejected. B) The calculated chi-square value is 0.66, and the critical value is 3.84. The null hypothesis cannot be rejected. C) The calculated chi-square value is 3.91, and the critical value is 5.99. The null hypothesis can be rejected. D) The calculated chi-square value is 3.91, and the critical value is 7.82. The null hypothesis cannot be rejected.

D) The calculated chi-square value is 3.91, and the critical value is 7.82. The null hypothesis cannot be rejected.

The researchers calculated a chi-square value of 29.25. If there are three degrees of freedom and the significance level is p=0.05, which of the following statements best completes the chi-square test based on Table 5-6? A) The critical value is 0.05, and the null hypothesis cannot be rejected because the calculated chi-square value is greater than the critical value. B) The critical value is 0.05, and the null hypothesis can be rejected because the calculated chi-square value is greater than the critical value. C) The critical value is 7.82, and the null hypothesis cannot be rejected because the calculated chi-square value is greater than the critical value. D) The critical value is 7.82, and the null hypothesis can be rejected because the calculated chi-square value is greater than the critical value.

D) The critical value is 7.82, and the null hypothesis can be rejected because the calculated chi-square value is greater than the critical value.

Himalayan rabbits are a breed of rabbits with highly variable fur color. If genetically similar rabbits are raised in environments that have different temperature conditions, the rabbits can have different color patterns. Which of the following statements best explains how the fur color can be different in Himalayan rabbits raised under different temperature conditions? A) The genotype does not contribute to coat color in Himalayan rabbits. B) The phenotype determines the genotype of coat color in Himalayan rabbits. C) Different environments cause specific mutations in the genes controlling pigment production. D) The environment determines how the genotype is expressed.

D) The environment determines how the genotype is expressed.

The beta-2 adrenergic receptor is a membrane-bound protein that regulates several cellular processes, including the synthesis and breakdown of glycogen. The receptor binds specifically to the hormone epinephrine. The binding of epinephrine to the beta-2 adrenergic receptor triggers a signal transduction cascade that controls glycogen synthesis and breakdown in the cell. A simplified model of the signal transduction cascade is represented in Figure 1. Which of the following outcomes will most likely result from the inactivation of the beta-2 adrenergic receptor? A) The cellular concentration of cyclic AMP will increase. B) The enzymatic activity of protein kinase A will increase. C) The activation of glycogen phosphorylase will increase. D) The rate of glycogen synthesis in the cell will increase.

D) The rate of glycogen synthesis in the cell will increase.

A researcher claims that the incorporation of carbon dioxide into organic molecules during photosynthesis does not violate the second law of thermodynamics. Which of the following statements best helps justify the researcher's claim? A) Organisms contain enzymes that lower the activation energies of specific chemical reactions B) An ecosystem is formed by the interaction of a community of organisms with their surrounding environment. C) Photosynthetic organisms use the organic molecules during photosynthesis for growth and repair. D) The total system that includes photosynthetic organisms and the Sun become less ordered over time.

D) The total system that includes photosynthetic organisms and the Sun becomes less ordered over time.

Which of the following questions would be most useful to researchers trying to determine the role of meiosis in the F2 phenotypic frequencies based on Figure 5-1 and Table 5-1? A) What is the molecular mechanism underlying the dominance of erect petals and long pollen? B) Which phenotypes give pea plants the highest level of fitness: erect or hooded petals and long or round pollen? C) How do the phases of meiosis differ between sweet pea plants and other organisms? D) What is the recombination frequency between the genes for petal shape and pollen shape?

D) What is the recombination frequency between the genes for petal shape and pollen shape?

G proteins are a family of receptor proteins that are involved in transmitting signals from outside a cell to inside a cell. When a signaling molecule binds to a G protein, the G protein is activated. The G protein then activates an enzyme that produces a second messenger called cAMP. Which of the following describes a critical role of cAMP during the transduction stage of a G protein signal transduction pathway? A) cAMP carries the signal to the nucleus of the cell and results in new sequences of nucleotides being added to the cell's DNA. B) cAMP binds the extracellular signal molecule and carries it to the intracellular target specified by the signal. C) cAMP modifies a specific monomer so that it can be added to an elongating structural macromolecule. D) cAMP results in the activation of an enzyme that amplifies the signal by acting on many substrate molecules.

D) cAMP results in the activation of an enzyme that amplifies the signal by acting on many substrate molecules.

What is the protein synthesized at specific times during the cell cycle that associates with a kinase to form a catalytically active complex?

D) cyclin

Plants contain meristems whose only function is to

D) divide

The human X and Y chromosomes

D) include genes that determine an individual's sex

Imagine looking through a microscope at a squashed onion root tip. The chromosomes of many of the cells are plainly visible. In some cells, replicated chromosomes are aligned along the center (equator) of the cell. These particular cells are in which stage of mitosis?

D) metaphase

Which of the following models shows how cholesterol molecules most likely interact with the phospholipid by layer of a cells plasma membrane?

D) they r embedded in the phospholipid bilayer

Genetic engineering techniques can be used when analyzing and manipulating DNA and RNA. Scientists used gel electrophoresis to study transcription of gene L and discovered that mRNA strands of three different lengths are consistently produced. Which of the following explanations best accounts for this experimental result?

D. Pre-mRNA of gene L is subject to alternative splicing, so three mRNA sequences are possible.

Figure 1. Effect of environmental temperature on body temperature of selected animals Which of the following statements is most consistent with the data in Figure 1 ?

D. Snakes display behaviors that allow them to absorb or radiate heat as required.

Which of the following correctly identifies the dependent variable and the independent variable for the experiment? Table 1. Response of ground squirrels to recorded vocalizations

D. The independent variable is the type of alarm, and the dependent variable is the percent of squirrels responding.

The figure above shows a model of a ligand precursor being cleaved to produce an active ligand that binds to a specific receptor. Which of the following is most likely to reduce the binding of the active ligand to its receptor? A. A change in the cytoskeletal attachment of transmembrane proteins B. The presence of a large amount of the precursor form of the ligand C. An increase in the ratio of the number of unsaturated to the number of saturated fatty acid tails of the membrane lipids D. A mutation in the receptor gene that causes a substitution of a charged amino acid for a nonpolar amino acid in the ligand binding site of the receptor

D. A mutation in the receptor gene that causes a substitution of a charged amino acid for a nonpolar amino acid in the ligand binding site of the receptor

Endothermy vs. Ectothermy-

Endothermy- warmed by metabolically generated heat, (humans, birds, insects)..warm blooded Ectothermy- heat from external sources (reptiles, fishes)

Different polysaccharides are used by plants for energy storage and structural support. The molecular structures for two common polysaccharides are shown in Figure 1. Starch is used by plants for energy storage, and cellulose provides structural support for cell walls. The monomer used to construct both molecules is glucose. A study determined the effect of two different digestive enzymes, A and B, on these two polysaccharides. Table 1 presents the data from the study. Mammals do not produce digestive enzyme B. However, sheep and cattle are two types of mammals that contain microorganisms in their digestive tract that produce enzyme B. Which of the following would most likely occur if cattle lost the ability to maintain a colony of microorganisms in their digestive tract?

D. Cattle would no longer be able to use cellulose as a primary source of glucose.

Researchers investigating the regulation of neurotransmitter release from presynaptic neurons proposed a model (Figure 1) in which CDK5, a protein expressed in axon terminals, inhibits the movement of synaptic vesicles to the presynaptic membrane. To test their model, the researchers used a modified version of green fluorescent protein (GFP*). In slightly alkaline conditions, GFP* exhibits a bright green fluorescence. In acidic conditions, GFP* exhibits no fluorescence. Using standard techniques, the gene encoding is easily introduced into living cells. By engineering the expression of GFP* in laboratory-cultured nerve cells, the researchers found that a bright green fluorescence was exhibited only when a presynaptic neuron was given a certain stimulus. Which of the following observations best supports the hypothesis that negatively regulates neurotransmitter release? A. Introduction of CDK5 protein into neurons results in the movement of synaptic vesicles to the plasma membrane in the absence of any stimulus. B. Uptake of a gene encoding CDK5 by neurons results in the movement of synaptic vesicles to the plasma membrane in the absence of any stimulus. C. Suppression of CDK5 expression in neurons inhibits the movement of synaptic vesicles to the plasma membrane in response to a specific stimulus. D. Inhibition of CDK5 activity in neurons increases the movement of synaptic vesicles to the plasma membrane in response to a specific stimulus.

D. Inhibition of CDK5 activity in neurons increases the movement of synaptic vesicles to the plasma membrane in response to a specific stimulus.

Thyroxin is a hormone that increases metabolic activities within various tissue targets. Low levels of circulating thyroxin trigger the secretion of thyroid-stimulating hormone (TSH) from the anterior pituitary. TSH secretion then stimulates thyroxin production and release by the thyroid gland. The increased level of circulating thyroxin inhibits further secretion of TSH from the anterior pituitary. Based on the information provided, which of the following can most likely be concluded about the TSH-thyroxin loop? A. A person taking thyroxin to supplement low thyroxin secretion will produce more TSH. B. Increased thyroxin production would cause elevated ribosomal activity in the anterior pituitary. C. The structure of the loop would lead to elevated thyroid and tissue activity due to positive feedback. D. The feedback mechanism would maintain relatively constant levels of thyroxin throughout tissue targets.

D. The feedback mechanism would maintain relatively constant levels of thyroxin throughout tissue targets.

Which feature of model 1 best illustrates how biological information is coded in a DNA molecule?

D. The linear sequence of the base pairs

In response to elevated blood glucose levels, beta (β) cells in the pancreas release insulin, a regulatory hormone. Insulin signals body cells to take up glucose from the blood, which returns blood glucose levels back to normal. Type 1 diabetes is an autoimmune disorder that destroys β-cells, resulting in elevated blood glucose levels. Researchers have proposed that diabetes could be treated by implanting human embryonic stem cells (hESCs) that have been induced to develop into β-cells (hESC-β). To test the proposed treatment, the researchers set up two groups of genetically identical mice and implanted the mice from one group with hESC-β cells. Several weeks after the hESC-β implant, both groups of mice were given a drug (STZ) that selectively destroys the naturally occurring mouse β-cells but does not affect the implanted hESC-β cells. Figure 1 shows a comparison of average blood glucose levels in both groups of mice. A. The mouse with an hESC-β implant demonstrated a decrease in blood glucose levels for the duration of the experiment. B. The mouse with an hESC-β implant demonstrated an increase in blood glucose levels before STZ treatment. C. The mouse with an hESC-β implant successfully regulated blood glucose levels by regenerating its naturally occurring β-cells. D. The mouse with an hESC-β implant successfully regulated blood glucose levels after STZ treatment but not after the implant was removed.

D. The mouse with an hESC-β implant successfully regulated blood glucose levels after STZ treatment but not after the implant was removed.

Difficulties to building a phylogenetic tree-

DNA database, analyze data for 50 species... 3 x 10^76 ways

Which of the following best describes the processes occurring between the mouse populations and their environments?

Dark color is selected for in mice from the West, Mid, and East populations.

three common modes of asexual reproduction

budding, regeneration, parthenogenesis

RFLP (restriction fragment length polymorphisms)

Different in each individual (except identical twins), unique to each person and are used to determine paternity or rape and murder cases

A model of crossing over during gamete formation is shown in Figure 1. Figure 1. Model of crossing over during meiosis Based on Figure 1, which of the following questions could best be addressed?

Does synapsis of homologous chromosomes in the parent cell contribute to an increase in genetic diversity in the daughter cells?

Which of the following describes a key difference among the 20 amino acids that are used to make proteins?

Due to having nonpolar R-groups, 10 of the 20 amino acids are hydrophobic. Interactions between hydrophobic amino acids play an important role in determining protein structure and function.

10. Which of the following correctly describes a possible phenotype of an organism? a. XX b. AaBbCC c. Alive d. Dead e. Orange

23. Why are Drosophila (fruit flies) used as model organisms in the study of genetics? a. They are cheap b. They can experience approximately 75% of diseases that humans experience c. They have a short reproduction cycle d. They have a high reproduction rate e. All of the above

24. When does an aneuploidy occur? a. Incorrect number of alleles b. Incorrect number of sex cells (gametes) c. Incorrect number of somatic (body) cells d. Incorrect number of nucleotides e. Incorrect number of chromosomes

25. Which of the following is *not* a polygene? a. Eye color b. Skin color c. Weight d. Height e. None of the above

As a teenager, Amy often changed her wardrobe, her hair color, and the decorations in her bedroom. These actions are most strongly connected with Erik Erikson's theory of (A) moral development (B) sexual development (C) social development (D) cognitive development (E) identity development

Studies have shown that identical twins raised together are more similar in relation to when they meet normative physical milestones than identical twins raised apart. Studies have also shown that identical twins are more similar in relation to when they meet normative physical milestones than ordinary siblings. What research method and explanation best fit the studies and their results? (A) Case studies, because heredity is more important than environment in development. (B) Correlational research, because environment is more important than heredity in development. (C) Experiments, because both heredity and environment are important in development. (D) Case studies, because environment is more important than heredity in development. (E) Correlational research, because both heredity and environment are important in development.

Which of the following scenarios best describes the relationship between temperament and child-parent relationships? (A) Garrett's parents reward him for having an easy temperament, so he remains an easy child. (B) Stanley has an easy temperament, which has made him more sensitive to differences in parenting. (C) Anthony has a difficult temperament, which has made him less sensitive to differences in parenting. (D) Fred has a slow-to-warm-up temperament, which has led his parents to be distant with him. (E) Sammy has a difficult temperament, but his parents love and care for him anyway.

A scientist determined the rate of an enzyme-catalyzed reaction by measuring the amount of product formed over time. The following curve was generated from the data collected. During which time interval is the reaction rate lowest? A 0-1 minute B 1-2 minutes C 2-3 minutes D 3-4 minutes E 4-5 minutes

E 4-5 minutes

For the following questions: Graphs I-IV depict the effect of pH on the activity of four different hydrolytic enzymes. Graphs representing enzymes sensitive to changes in pH include which of the following? A I only B IV only C II and III only D III and IV only E I, II, and III only

E I, II, and III only

Which of the following is true concerning cancer cells?

E) A, B, and C

What is the protein maintained at constant levels throughout the cell cycle that requires cyclin to become catalytically active?

E) Cdk

The karyotype of one species of primate has 48 chromosomes. In a particular female, cell division goes awry and she produces one of her eggs with an extra chromosome (25). The most probable source of this error would be a mistake in which of the following?

E) Either anaphase I or II

A given organism has 46 chromosomes in its karyotype. We can therefore conclude which of the following?

E) Its gametes must have 23 chromosomes.

Which term describes centrioles beginning to move apart in animal cells?

E) prophase

Which of the following statements best explains the experimental results observed in Figure 1 ?

E. coli in lane C have been successfully transformed and contain additional genetic information.

What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell?

ER → Golgi → vesicles that fuse with plasma membrane

What is the most likely pathway taken by a newly synthesize proteins that will be secreted by a cell?

ER-> Golgi-> vesicles that fuse with plasma membrane

Which of the following best helps explain how the process represented in Figure 1 produces DNA molecules that are hybrids of the original and the newly synthesized strands?

Each newly synthesized strand remains associated with its template strand to form two copies of the original DNA molecule.

A scientist claims that Elysia chlorotica, a species of sea slug, is capable of photosynthesis. Which of the following observations provides the best evidence to support the claim? A

Elysia chlorotica grows when exposed to light in the absence of other food sources.

During a hot spring, the western white butterfly is found to have an unusually light wing pigmentation. What is the best reason for this altered phenotype? A. Change in alleles B. Independent assortment C. Environment D. Altered genes

Environment

Movement of solutes across a plasma membrane from a region of higher solute concentration to a region of lower solute concentration with the aid of proteins

Facilitated Diffusion

Warfarin is a drug used to treat certain blood clots. Warfarin blocks the formation of active form of vitamin K- dependent clotting factors. Based on the model, which of the following best predicts the effects of a warfarin on a patient?

Factor X will not be activated, which will prevent thrombin from forming.

What can scientists find once they determine the sequence of a DNA molecule? A. Gene B. Allele C. Plasmid D. Southern blot

Gene

Function will be disrupted by adding the urea and regained by removing the urea.

A population geneticist is conducting an investigation on a population of mice. The geneticist determines the genotypes for a particular trait of all of the mice in the population during generation 1 and then removes all of the mice with the genotype aa. The remaining members of the population are allowed to randomly mate with one another to produce generation 2 and future generations. A model of the investigation is shown in Figure 1. Each of the fifteen genotypes shown in generation 1 and generation 2 represents 100 mice. Figure 1. Model of effect of selective mouse removal on a population Which of the following best illustrates the change in the frequencies of the A and a alleles from generation 1 to generation 2 and to future generations, assuming Hardy-Weinberg equilibrium is present after generation 1 ?

Future generations will eventually completely lose the a allele from the gene pool. There will not be any new individuals with the aa genotype.

Concerns about genetically modified foods include all of the following except A. GM foods are not labeled differently than non-GM foods. B. GM plants may threaten beneficial insects. C. GM plants cause overuse of weed killer. D. GM foods produce high yields.

GM foods produce high yields.

relationship between drought and beak size in finches

Galapagos experienced drought => small seeds in short supply & large seeds easy to come by => finches with larger beaks can penetrate larger seeds => large beaked finches had higher survival rate => small beaked finch population greatly reduced => next generation of finches saw greater number of large beaks (natural selection demonstrated)

What is the term for the process of changing a gene to treat a medical disease or disorder? A. Pedigree B. Gene mapping C. Gene therapy D. Genomics

Gene therapy

What act did the United States Congress pass to protect Americans against discrimination based on their genetic information? A. Medical Device Act B. Family Smoking Prevention and Tobacco Control Act C. Genetic Information Nondiscrimination Act D. Food and Drug Administration Safety and Innovation Act

Genetic Information Nondiscrimination Act

Cyanide bonds to at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found in the

Mitochondria

The Tomb of the Unknowns serves as a place for the remains of unidentified soldiers. Today, each soldier who enters into duty is required to provide a DNA sample, so that soldiers killed in service can be identified. What term best pertains to this issue? A. Genetic ownership B. Genetic modification C. Segregation D. Pedigree

Genetic ownership

Geologic events such as mountain building can directly affect biodiversity. The Sino‑Himalayan fern, Lepisorus clathratus is widely distributed on the Qinghai‑Tibetan plateau. If geologic events lead to a series of new mountain ranges that divide the plateau into several discrete valleys, which of the following best describes how the L. clathratus population would be affected?

Geographic isolation will create separate gene pools, leading to speciation over time.

Bases on the B-globin alignment, identify the best hypothesis about how humans are related to monkeys and gibbons.

Gibbons are more closely related to humans than monkeys are because the gibbons B-globin sequence is a closer match with the human sequence.

The immediate energy source that drives ATP synthesis by ATP synthase during oxidative phosphorylation is the

H+ concentration across the membrane holding ATP synthase.

Which of the following molecules would contain a polar covalent bond

H2O

A model showing the cells in anaphase 1 and anaphase 2 of meiosis during a nondisjunction event is shown in Figure 1. Figure 1. Model of a nondisjunction event Which of the following best predicts the effect of the chromosomal segregation error shown in Figure 1?

Half of the resulting gametes will have the correct number of chromosomes, and the other half will have an incorrect number of chromosomes.

Which of the following best predicts why humans and mice have identical telomeric repeat sequences?

Humans and mice share a recent common ancestor that had the 5′-TTAGGG-3′′ repeat sequence in its telomeres.

Horses and donkeys mate successfully to produce mules which are always sterile. Which genetic isolating mechanism is involved here to prevent horses and donkeys from becoming a single species?

Hybrid infertility

Crossing dissimilar individuals to bring together the most desirable characteristics of both in their offspring is known as A. inbreeding. B. biotechnology. C. bioinformatics. D. hybridization.

Hybridization

Ice floats because

Hydrogen bonding spaces the molecules farther apart, creating a less dense structure.

G1 is represented by which number(s)?

I and V

Which of the following best explains how this model illustrates DNA replication of both strands as a replication fork moves?

I is synthesized continuously in the 5′ to 3′ direction, and III is synthesized in segments in the 5′ to 3′ direction.

In the figure above, mitosis is represented by which number?

Which statement provides the evidence to justify the claim that signal transduction May result in an altered phenotype?

If the SRY gene is absent or nonfunctional, the embryo will exhibit female sexual development.

Which of the following best predicts what will happen to the blood glucose level if the person has another meal at 5pm?

Immediately after the meal, the blood glucose lever will increase, and then insulin will be secreted to counter the increase.

Based on the data in Figure 1, which of the following would most affect the allelic frequencies of the populations on Isabela and Butuan?

Immigration of individuals from Metro Manila into the two populations

There are genetic crosses in which neither of two alleles is dominant over the other. In these crosses, the phenotype is a blend of the two alleles. These crosses are described as A. non-Mendelian inheritance. B. multiple alleles. C. codominant. D. incomplete dominance.

Incomplete dominance

A group of researchers noticed that using a particular drug to treat cancer in mice would reduce the size of the tumor, but some of the tumor cells appeared to be resistant to the drug since some of these cells would increase in number over time. The researchers wish to increase the reliability of their experimental observations before investigating new claims that chemotherapy-resistant tumors are an example of continuing evolution. Of the following, which is the best next step the researchers might take to increase the reliability of their evidence?

Increasing the number of trials and the number of mice in each treatment group

Researchers investigate the transport of a certain protein into cells by endocytosis. In an experiment, the researchers incubate the cells in the presence of the protein and measure the amount of the protein that is absorbed into the cells over a five-minute period. Based on their observations, what should the researchers do to further clarify how the availability of the protein outside the cells affects the rate of endocytosis of the protein?

Incubate the cells in the absence of the protein.

Based on their observations, what should the researchers do to further clarify how the availability of the protein outside the cells affects the rate of endocytosis of the protein?

Incubate the cells in the presence of several different concentrations of the protein.

What term defines why genetic variations are present in organisms even when they have the same parents? A. Punnett square B. Dependent assortment C. Genetics D. Independent assortment

Independent Assortment

Heterochromatin

Is a tightly packed form of DNA, because it is tightly packed it is inaccessible to polymerases and is not transcribed

rRNA

Involved in translation, makes up ribosome

A compound that prevents the separation of the homologous chromosomes in anaphase I is being studied. Which of the following questions can be best answered during this study?

Is there a pattern to the movement of homologous chromosomes in the presence of this compound?

It changes the three-dimensional structure of the active site so that ALAD is no longer compatible with its substrate.

Which of the following statements is not true of a pentose?

It has the formula C3H12O5

Which of the following conclusions about increasing the number of folds in the inner mitochondrial membrane is best supported by the results of the experiment?

It increases the surface area available for ATP production, which results in faster cell growth.

In an experiment, researchers compared the growth of two different plants, plant X and plant Y. The researchers maintained the plants under nearly identical conditions and observed that plant X grew faster than plant Y. The researchers also observed that the inner mitochondrial membranes of plant X had more folds than did those of plant Y. Which of the following conclusions about increasing the number of folds in the inner mitochondrial membrane is best supported by the results of the experiment?

It increases the surface area available for ATPATP production, which results in faster cell growth.

Figure 1 shows a short segment of a double-stranded nucleic acid molecule. Which of the following statements is correct about the molecule shown in Figure 1 ?

It is DNA because of the nucleotides present. The figure indicates that one of the nucleotides is thymine. Thymine is found in DNA and not in RNA.

Which of the following best describes the component that metformin represents in a signal transduction pathway that regulates glucose production in the liver?

It is a ligand that activates the signal transduction pathway of the activation of AMPK.

Which of the following is true of cellulose?

It is a major structural component of plant cell walls.

Which of the following statements is true regarding the molecule illustrated in Figure 5.2?

It is a saturated fatty acid and a diet rich in this molecule may contribute to atherosclerosis.

Which of the following claims about the origin of the euglenid chloroplast is best supported by the three-membrane structure of the envelope?

It originated from the incorporation of a photosynthetic prokaryote into a eukaryotic cell by two endosymbiotic events.

Which of the following is not true of an asymmetrical carbon atom?

It is found in all cis-trans isomers

When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated?

It is lost to the environment.

When an individual is exercising heavily and when the muscle becomes oxygen-deprived, muscle cells convert pyruvate to lactate. What happens to the lactate in skeletal muscle cells as oxygen becomes available again?

It is taken to the liver and converted back to pyruvate.

Some archaea are able to live in lakes with pH values of 11. How does pH11 compare with the pH 7 typical of your body cells?

It is ten thousand times more basic than pH 7.

Which of the following claims about the origin of euglenid chloroplast is best supported by the 3- membrane structure of the envelope?

It originated from the incorporation of a photosynthetic prokaryote into a eukaryote cell by the TWO Endosymbiotic events.

Which of the following statements is/are true regarding the chemical reaction illustrated in Figure 5.5?

It results in a peptide bond.

In an experiment, researchers provided a radiolabeled amino acid to living plant cells. After one hour, the researchers determined the amount of the radiolabeled amino acid that was in each of several subcellular compartments. The results of the experiment are represented in the table. RELATIVE AMOUNTS OF RADIOLABELED AMINO ACID NucleusMitochondriaEndoplasmic ReticulumCytosol2.12.71.91 Which of the following conclusions about the radiolabeled amino acid is best supported by the results of the experiment?

It was mostly incorporated into proteins that regulate and manage metabolic reactions.

Which of the following conclusions about the radiolabeled amino acid is best supported by the results of the experiment?

It was mostly incorporated into proteins that regulate and manage metabolic reactions.

You have a friend who lost 7 kg (about 15 pounds) of fat on a regimen of strict diet and exercise. How did the fat leave her body?

It was released as CO2 and H2O.

Which of the following statements best helps justify the inclusion of test tube 5 in the experiment?

It will act as a control for test tube 6 by showing the effect of the presence or absence of the enzyme.

Which of the following statements best helps justify the inclusion of group 2 as one of the controls in the experiment?

It will show whether the changes observed in group 1 depend on the metabolic activity of soil bacteria.

Which of the following statements best helps justify the inclusion of group 2 as one of the controls in the experiment?

It will show whether the changes observed in group one depend on the metabolic activity of soil bacteria.

Which of the following statements is not true of cellulose?

Its monomers are glucose with nitrogen-containing appendages.

Which of the following shows a complete diploid set of chromosomes grouped together in pairs, arranged in order of decreasing size? A. Sex chromosome B. Genome C. Gene map D. Karyotype

Karyotype

There are two species of elephant seals: northern elephant seals, Mirounga angustirostris, found off the western coast of North America from Baja California to the Gulf of Alaska, and southern elephant seals, M. leonina, found in the southern oceans. Hunting in the nineteenth century has been blamed for a drastic reduction in the northern elephant seal population. Even though the population has rebounded following restrictions on seal hunting, genetic variation is greatly reduced in the northern species compared to that in the southern species. Which of the following conditions of Hardy-Weinberg equilibrium was most likely not met in the northern elephant seal population following overhunting?

Large population size

The R group or side chain of the amino acid serine is -CH2-OH. The R group or side chain of the amino acid leucine is -CH2-CH-(CH3)2. Where would you expect to find these amino acids in a globular protein in aqueous solution?

Leucine would be in the interior, and serine would be on the exterior of the globular protein.

DNA replication

Making the exact replica of the DNA molecule by semiconservative replication

Based on the sample means, which of the following conclusions about the cells in the growing root tips of Zea mays seedlings is best supported by the results of the experiment?

More cells are produced per unit of time in the root tips growing in compact sand than in the root tips growing in loose sand.

Mollusk fossils were excavated and collected from a coastal cliff. Scientists studying the fossils observed patterns of changing shell shape in the mollusks. The scientists identified a period of stability or stasis, followed by rapid change, and then stasis again with regard to shell shape. Which of the following statements best predicts the result of a comparison between the fossils found before and after the period of rapid change?

Most of the species found in the first static period will be absent in the second static period.

Which of the following statements about the cytoskeleton is true?

Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other

How nitric oxide is affected by Viagra-

NO functions as a local regulator and neurotransmitter When O2 decreases, edothelial cells release NO into blood vessels...after diffusing to surround muscle cells, acts as enzyme to relax cells (vaodialation) In males, NO vasodilation enables sexual function by increased blood flow to the penis, sustains erection

Students created a model showing one possible mechanism for speciation in which a geographic barrier separated one large population into two smaller populations, A and B. Over time, populations A and B developed into two distinct species. The model is shown in Figure 1.

Natural selection acted on variation that was present in both populations A and B, and the lack of gene flow eventually led to the formation of two new species.

Exons

Needed, coding sequence

A researcher found a mutation that resulted in the PFK enzyme being unable to bind ATP to the allosteric site. Which of the following best predicts the effect of the mutation?

Negative feedback regulation does not occur, so the enzyme will be active when glycolysis is not needed.

In chloroplasts, ATP is synthesized from ADP plus inorganic phosphate (Pi) in a reaction catalyzed by ATP synthase molecules that are embedded in the thylakoid membrane. Which of the following statements provides evidence to support the claim that no ATP will be synthesized in the absence of a proton gradient across the thylakoid membrane?

No ATP is synthesized when channel proteins that allow the free passage of protons are inserted into the thylakoid membrane

Sometimes, gametes have an abnormal number of chromosomes, which leads to a disorder of chromosome numbers. Gametes can end up with an abnormal number of chromosomes because of _____, an event that most often occurs during meiosis. A. segregation B. codominance C. nondisjunction D. karyotyping

Nondisjunction

Introns

Not needed, noncoding sequence

If an enzyme is added to a solution where its substrate and product are in equilibrium, what will occur?

Nothing, the reaction will stay at equilibrium.

Which test tubes are controls in the experiment?

Test tubes 1,3,5,7

We can be sure that a mole of table sugar and a mole of Vitamin C are equal in their

Number of molecules

Some scientists propose that due to human activity and climate change, a sixth mass extinction has already begun. Select the best alternate hypothesis to support this claim.

Observed modern extinction rates will resemble the rates found early in previous extinctions.

enantiomers

One of two compounds that are mirror images of each other and that differ in shape due to the presence of an asymmetric carbon.

Phosphorous (P) is an important nutrient for plant growth. Figure 1 shows Arabidopsis thaliana plants grown under phosphorus‐sufficient (left) (much taller) and phosphorus‐starved (right) (much smaller) conditions for six weeks. most likely reason for the difference in leaf growth?

Phosphorus is used to make nucleic acids and certain lipids. Without phosphorus atoms, nucleic acids and lipids cannot be made for the plant to use for growth.

Based on figure 1, which of the following statements best predicts the effect that a change from a moderately acidic environment, PH near 6, to a basic environment will have on peroxidase activity?

Peroxidase activity will decrease.

Researchers investigated the influence of environmental pH on the activity of peroxidase, an enzyme that catalyzes the conversion of hydrogen peroxide to water and oxygen gas. In an experiment, the researchers added a hydrogen peroxide solution containing guaiacol to several identical test tubes and adjusted the solution in each test tube to a different pH. The researchers included the guaiacol because it caused the solutions to change color as the reactions proceeded, which the researchers relied on for measuring reaction rates. Finally, the researchers added the same amount of peroxidase to each test tube and measured the rate of each reaction at 23°C. The results of the experiment are represented in Figure 1. Based on Figure 1, which of the following statements best predicts the effect that a change from a moderately acidic environment (pH near 6) to a basic environment will have on peroxidase activity?

Peroxidase activity will decrease.

Environmental conditions can affect gene expression, changing an organism's A. phenotype. B. genotype. C. fertilization. D. alleles.

Phenotype

In pea plants, purple flower color is dominant to red flower color and long pollen grains are dominant to round pollen grains. Researchers crossed two pure-breeding lines of the pea plants to investigate whether the genes controlling flower color and pollen shape segregate independently. The procedure for the genetics experiment is summarized in Figure 1. Figure 1. Summary of a genetics experiment using pea plants Which of the following tables best shows the expected values in the F2 generation for a chi-square goodness-of-fit test for a model of independent assortment?

Phenotype Expected Purple, long 1199 Purple, round 400 Red, long 400 Red, round 133

Which of the following statements best describes the relationship between photosynthesis and respiration?

Photosynthesis stores energy in complex organic molecules, whereas respiration releases it.

Phylogeny and Taxonomy, main picture and mechanism

Picture- phylogentic tree ( model showing history of a group of organisms) mechanism- cladistics, method of hypothesizing relationships among organisms ex: cladogram, members of same species share unique characteristics not present in ancesters (ex. fur in mammals)

An experiment crosses an F1 generation of red-flowered (RR) plants and white-flowered (WW) plants. What is the color of the F2 generation if the allele for color is characteristic of incomplete dominance? A. White B. Red C. Pink D. Blue

Pink

Which of the following best predicts the effect of adding this inhibitor to a culture of plant cells?

Plant cells will be unable to perform glycolysis due to the inhibitor and will die.

What cells have a cell wall

Plants and Bacterial

What is the term for small circular DNA molecules found in bacteria, which are often used in recombinant DNA studies? A. Genetic markers B. Southern blots C. Plasmids D. Clones

Plasmids

T and C

Pyrimidines nitrogen bases

Elongation of transcription

RNA polymerase adds nucleotides to the 3' end of a growing chain

The figure shows a representation of a protein embedded in a cell membrane. The numbers indicate different structural regions of the protein. Based on the figure, which of the following statements best describes the relationship between regions 1 and 2 of the protein?

Region 1 is hydrophilic because it interacts with an aqueous environment, whereas region 2 is hydrophobic because it interacts with the interior of the membrane.

Intravenous (IV) therapy is used for fluid replacement in instances of dehydration in humans and other animals. One type of IV fluid is essentially a saltwater solution. To determine the best concentration for therapy in people, a team of students is researching the effects of solutions of different salt concentrations on red blood cells. The following observations were made from three different red blood cell samples viewed under a microscope. 0.3% Saline (Cells swell) 0.9% Saline (Cells unchanged) 1.5% Saline (Cells shrink) The team wants to extend the research project. What should the team of students do next to obtain data that are more conclusive?

Repeat the process with other salt concentrations.

The team wants to extend the research project. What should the team of students do next to obtain data that are more conclusive?

Repeat the process with other salt concentrations.

What should a team of students do next to obtain data that are more inclusive?

Repeat the process with other salt concentrations.

The innermost portion of the cell wall of a plant cell specialized for support is the

Secondary cell wall

Researchers investigated the influence of environmental pH on the activity of peroxidase, an enzyme that catalyzes the conversion of hydrogen peroxide to water and oxygen gas. In an experiment, the researchers added a hydrogen peroxide solution containing guaiacol to several identical test tubes and adjusted the solution in each test tube to a different pH. The researchers included the guaiacol because it caused the solutions to change color as the reactions proceeded, which the researchers relied on for measuring reaction rates. Finally, the researchers added the same amount of peroxidase to each test tube and measured the rate of each reaction at 23°C. The results of the experiment are represented in Figure 1. Which of the following actions will provide a negative control for the investigation?

Repeating the experiment using heat-denatured peroxidase

Which of the following actions will provide a negative control for the investigation?

Repeating the experiment using heat-denatured peroxidase.

Highly specific substances that cut DNA molecules into fragments are known as A. restriction enzymes. B. nitrogen bases. C. alleles. D. gene sequencers.

Restriction enzymes

What organelle translates DNA codes into proteins

Ribosome

Which of the following cellar structures are common to both prokaryotes and eukaryotes

Ribosomes

What is the most common route for membrane flow in the endomembrane system

Rough ER - transport vesicles - Golgi - vesicles - plasma membrane

Which of the following statements provides the best explanation of the processes illustrated in Figure 1 ?

Sections of the pre-rRNA are removed, and the mature rRNA molecules are available to combine with proteins to form the ribosomal subunits.

.What term defines the event when the alleles for each gene separate from each other so that each gamete carries only one allele for each gene? A. Characterization B. Segregation C. Genetics D. Principle of dominance

Segregation

Supportive Connective Tissue

STRONG AND DURABLE...support Cartilage- strong, flexible fibers in a rubbery substane (end of nose) Bone- strong, mineralized, osteoblasts deposit matrix of collagen

Which of the following is not a step in the process scientists use to copy a gene? A. DNA polymerase starts copying the region between the primers. B. As the DNA cools, primers bind to the strands. C. Scientists cool DNA, which fuses its two strands. D. The copies made by DNA polymerase can serve as templates to make more copies.

Scientists cool DNA, which fuses its two strands.

Humans use _____, which takes advantage of naturally occurring genetic variation, to pass desired traits on to the next generation of organisms such as dogs. A. inbreeding B. selective breeding C. segregation D. bioinformatics

Selective breeding

For sexually reproducing diploid parent cells, which of the following statements best explains the production of haploid cells that occurs in meiosis but not in mitosis?

Separation of chromatids occurs once, and there are two rounds of cell division in meiosis.

Operon

Set of genes and the switches that control the expression of those genes

Which of the following cellular deficiencies would most likely be related to these MT-ND1 mutations?

The cell is unable to complete reactions related to electron transport and ATP production.

A sex-linked gene is a gene located on a _______ chromosome. Sex-linked genes that are located on the Y chromosome are found only in _______. A. sex; males B. sex; females C. autosomal; males D. autosomal; females

Sex; males

Based on the information provided in Figure 1 and Figure 2, which of the following best predicts the effects of a mutation in the promoter of the TYR gene that prevents it from being transcribed?

Skin pigmentation will not be able to change, resulting in a negative selection pressure.

Plasmid

Small, circular extrachromosomal DNAs that are dispensable to bacteria cell

Four elements make up more than 96% of the mass of most living organisms. Which of the following is NOT one of those four elements?

Sodium (the four elements is CHON)

Another biologist alternatively hypothesizes that these types of molecules require channel and transport proteins that are embedded in the membrane in order to move across the membrane. Which of the following data would best refute this alternative hypothesis?

Sodium ions cannot move across the cell membrane with membrane protein activity is blocked.

Bacteria that contain plasmids are resistant to a wider range of antibiotics and are bacteria that contain no plasmids. Which of the following statements best establishes a connection between the observation and the researchers claim?

Some plasmids contain antibiotic resistant genes.

Which claim is most consistent with the information provided by the diagram and current scientific understanding of gene regulation and expression?

Some sequences of DNA can interact with regulatory proteins that control transcription.

A horse horse has 2N=64 and a donkey has 2N=62. the hybrid of these two species, mules have 63 chromosomes and are sterile. why are mules sterile?

Some chromosomes lack homologs and cannot undergo meiosis

In a particular region, a species of lizard lives in the lowlands. Even though there are numerous mountains in the region, the climate on the mountains is too cold for the lizards to survive. Scientists are concerned that the lowlands will become much warmer by the end of the twenty-first century and will become unsuitable for this lowland lizard species. Which of the following best predicts the impact on the lizard species if there is a gradual increase in the average temperatures found in both the lowlands and mountains in this region?

Some lizards will migrate to new habitats in the mountains and become isolated, leading to allopatric speciation.

Some plasmids contain antibiotic resistance genes.

Specimen 1 Specimen 2 Specimen 3 Specimen 4 Amino acid differences* 5 21 18 11 Percent of original carbon-14 remaining 38 73 25 11 Composition Sandstone Sandstone Limestone Shale DNA analysis 35% Guanine 28% Guanine 12% Guanine 29% Guanine *amino acid differences of a conserved protein compared with a fifth fossil specimen Which of the specimens indicated in the table is the oldest?

Specimen 4

Different polysaccharides are used by plants for energy storage and structural support. The molecular structures for two common polysaccharides are shown in Figure 1. Starch is used by plants for energy storage, and cellulose provides structural support for cell walls. The monomer used to construct both molecules is glucose. photo A study determined the effect of two different digestive enzymes, A and B, on these two polysaccharides. Table 1 presents the data from the study. Table 1. Effect of Enzymes A and B on Cellulose and Starch Test Tube Polysaccharide Added Enzyme Added Glucose Detected after 5 Minutes at 37°C 1 Cellulose A No 2 Cellulose B Yes 3 Starch A Yes 4 Starch B no Mammals do not produce digestive enzyme B. However, sheep and cattle are two types of mammals that contain microorganisms in their digestive tract that produce enzyme B. Based on Figure 1, which of the following best compares the atomic structures of starch and cellulose?

Starch and cellulose are composed of repeating glucose monomers; however, in cellulose every other glucose monomer is rotated 180 degrees.

Which of the following statements about the 5' end of a polynucleotide strand of RNA is correct?

The 5' end has a phosphate group attached to the number 5 carbon of ribose.

The degrees of relatedness in several native populations of prairie chickens in Marion and Jasper Counties in Illinois were determined. The degree of relatedness is inversely proportional to genetic diversity; that is, populations with a high degree of relatedness have less genetic diversity. Table 1 shows the collected data. Populations J1 through J5 are located in Jasper County. Populations M1 through M5 are located in Marion County. Numbers above 0.125 indicate a high degree of relatedness. Table 1. RELATEDNESS OF PRAIRIE CHICKEN POPULATIONS Population Degree of Relatedness J1 0.215 J2 0.215 J3 0.339 J4 0.280 J5 0.362 M1 0.305 M2 0.365 M3 0.199 M4 0.432 M5 0.405 Scientists claim that some of the populations in Marion County are at an increased risk of decline or extinction. Based on the data in table 1, which of the following best provides evidence to support this claim?

The M4 and M5 populations have the lowest genetic diversity of all populations.

Help Lilly AP Program AP Biology HomeAssessmentsProgress Dashboard Assessments AssignmentsProgressResults Unit 2 Progress Check: MCQ Start Date: 10/6/2019Due Date: — Topics and SkillsQuestions Your Performance 17/30 Active Transport of Ions 0/1 MC point Some membrane proteins help maintain the concentrations of ions inside a cell by transporting the ions across the cell's plasma membrane. Other membrane proteins form pores in the plasma membrane through which the ions can diffuse. A model showing the influence of membrane proteins on the movement of sodium (Na+) and potassium (K+) ions across a plasma membrane is presented in Figure 1. Figure 1. Section of a cell's plasma membrane, showing ion concentrations and membrane proteins Based on the model presented in Figure 1, which of the following changes will most likely result from a depletion of available ATP stores inside the cell?

The Na+Na+concentration inside the cell will increase.

Based on the model presented in Figure 1, which of the following changes will most likely result from a depletion of available ATPstores inside the cell?

The Na+concentration inside the cell will increase.

Mendel's theory of segregation was highly supported by examining all of the following pea plant generations except A. the P generation B. the F1 generation C. the F2 generation D. the P2 generation

The P2 generation

Figure 1 shows three amino acids that are part of a polypeptide chain. Figure 2 shows the same section of the chain after a mutation has occurred. -How might this change affect the structure and function of the protein?

The R-group of the new amino acid, valine, has different chemical properties than the R-group of cysteine. This will cause the protein to misfold and not function properly in the cell.

A group of mutations, known as MT-ND1, have been identified in mitochondrial DNA. These mutations are associated with a number of debilitating diseases stemming from the production of nonfunctional proteins in the mitochondria. Which of the following cellular deficiencies would most likely be related to these MT-ND1 mutations?

The cell is unable to complete reactions related to electron transport and ATPATP production. Answer D

As shown in Figure 1, an amino acid must have which of the following properties in order to be incorporated into a polypeptide?

The ability to form a covalent bond with both its NH2 group and its COOH group

Many mammals control their body temperature by sweating. Which property of water is most directly responsible for the ability of sweat to lower body temperature?

The absorption of heat by the breaking of hydrogen bonds

The active site of AChE is specific for acetylcholine, and only one substrate molecule can occupy the active site at a time.

The additional pigments absorb light at wavelengths that green algae cannot absorb; this may allow cyanobacteria to capture more light energy for photosynthesis than green algae can in certain areas.

Based on the data in Figure 1, which of the following is the best prediction of the mode of inheritance of red eyes in Japanese koi?

The allele for red eyes is inherited in an autosomal dominant pattern.

Based on the data in Figure 5-4, which of the following is the best prediction of the mode of inheritance of red eyes in Japanese koi? A) The allele for red eyes is inherited in an autosomal dominant pattern. B) The allele for red eyes is inherited in an autosomal recessive pattern. C) The allele for red eyes is inherited in an X-linked recessive pattern. D) The allele for red eyes is inherited in an X-linked dominant pattern.

The allele for red eyes is inherited in an autosomal dominant pattern.

Which of the following best predicts the immediate result of adding more substrate to the reaction mixture at the point indicated by the arrow in figure 1?

The amount of product will increase until the reaction reaches equilibrium point or until the substrate is used up by the reaction.

Which of the following best predicts the immediate result of adding more substrate to the reaction mixture at the point indicated by the arrow in Figure 1?

The amount of product will increase until the reaction reaches its equilibrium point or until the substrate is used up by the reaction.

When a plant cell, such as one from a peony stem, is submerged in a very hypotonic solution, what is likely to occur?

The cell will become turgid

Which of the following statements correctly describes the normal tonicity conditions for typical plant and animal cells?

The animal cell is in an isotonic solution, and the plant cell is in a hypotonic solution

The island was surveyed again in 2015, and scientists determined that the giant kangaroo rats originally in population A are now to be considered as a new species. Which of the following best explains the mechanism that caused this speciation event in the giant kangaroo rats of population A?

The animals in population A were reproductively isolated from those in populations B, C, and D.

Which statement is true of all atoms that are anions?

The atom has more electrons than protons.

The cell is unable to complete reactions related to electron transport and ATP production.

A cell needs to metabolize the substrate illustrated in Figure 1 for a vital cellular function. Which of the following best explains the long-term effect on the cell of splicing that yields only enzyme C mRNA?

The cell will die because it is unable to metabolize the substrate without enzyme A, which is structurally specific for the substrate shown

Based the information provided, which of the following statements best describes why starch and cellulose provide different functions in plants?

The differences in the assembly and organization of the monomers of these two polymers result in different chemical properties. -The identical orientations of the glucose monomers in starch create a polysaccharide with alpha bonds that is easy to break down into glucose for energy use. The alternating orientations of the glucose monomers in cellulose create beta bonds that produce a rigid polymer that is difficult to digest for energy use.

A flask containing photosynthetic green algae and a control flask containing water with no algae are both placed under a bank of lights, which are set to cycle between 12 hours of light and 12 hours of dark. The dissolved oxygen concentrations in both flasks are monitored. Predict what the relative dissolved oxygen concentrations will be in the flask with algae compared to the control flask.

The dissolved oxygen in the flask with algae will be higher in the light, but lower in the dark.

What trait, dominant or recessive, will be expressed if an organism has one dominant allele and one recessive allele? A. The organism will lack that trait completely. B. Both the dominant and recessive traits C. The dominant trait D. The recessive trait

The dominant trait

Data from the Human Genome Project has raised a number of ethical and legal questions regarding all of the following except A. who should have access to personal genetic information. B. discrimination against people with genetic abnormalities. C. the effect of genetic projects on the environment. D. who owns and controls genetic information.

The effect of genetic projects on the environment

Frameshift mutation

The entire reading frame is altered

In a certain small mammal, fur color is controlled by a pair of alleles, with B being dominant over b. The genotypes BB and Bb result in dark-colored fur, the genotype bb results in light-colored fur. A population of the species has the following allele frequencies: B=0.85 and b=0.15. If a fire caused the surface of the ground in the habitat of the species to become darker in color, which of the following claims about the impact on the allele frequencies in this population is most reasonable?

The frequency of the B allele will increase because light-colored individuals will be more visible to predators.

The researchers built an enclosure to prevent migration into and out of the O'Neill rock pocket mouse population for a period of two years. Which of the following best predicts the effect of the enclosure on the O'Neill population?

The frequency of the MC1RD allele will decline due to natural selection.

A scientist is studying the impact of mutagens on genetic variation in mice. In an experiment, the scientist creates two groups of twenty highly inbred mice. Because the mice are highly inbred, they are essentially identical to one another. One group is given food with an added substance that is known to be a mutagen. The second group is fed the same food without the mutagen. After several generations, both groups of mice are given a new type of food that is harder to digest than the previous food. After rearing five additional generations of the mice on this new food, the two groups are assessed for how efficiently this new food is digested. Which of the following is the most reasonable prediction about the results of the experiment?

The group of mice fed the mutagen will show a greater ability to digest the food, because the higher genetic variation within the group makes it more likely that some individuals will have a combination of genes better adapted to the new food.

Which of the following best explains a possible mechanism that would enable the hormone to efficiently reach all of the target cells in the body?

The hormone is released into the bloodstream where it can be transported to all cells with the correct receptors.

Which of the following models best demonstrates the arrangement of hydrogen bonds between adjacent water molecules?

The hydrogen bonds between these water molecules correctly show the attractive force between the hydrogen atom of one water molecule and the oxygen atom of the adjacent water molecule.

A famous study from the nineteenth century involves the peppered moth, Biston betularia, commonly found in Great Britain and Ireland. At that time, the moths, normally white with black speckles, known as the peppered variety, became less common than the solid black variety. The population was predominantly black throughout the nineteenth century. By the end of the twentieth century, the peppered version of the moth was again more common than the black version. Which of the following best explains the phenotypic pattern in the moths over time?

The increased air pollution of the nineteenth century due to the use of coal led to a darkening of surfaces from soot. The darker backgrounds conferred a selective advantage to the black variety, as described by natural selection. A shift to less polluting fuel in the twentieth led to cleaner air and a lightening of the moth's normal habitat.

Which of the following best predicts what will happen to the lysosomal enzymes if the proteins that transport H+ ions from the cytosol into the lysosome are damaged?

The lysosomal enzymes will NOT become active, since there will be no active transport of H+ ions.

Lysosomes digest food particles brought into a cell by endocytosis. After a vesicle containing food particles fuses with a lysosome, H+ ions are transported into the lysosome from the cytosol. This significantly lowers the pH of the lysosome relative to the cytosol and activates the enzymes that digest the particles. Which of the following best predicts what will happen to the lysosomal enzymes if the proteins that transport H+ ions from the cytosol into the lysosome are damaged?

The lysosomal enzymes will not become active, since there will be no active transport of H+ ions.

lysosomes digest food particles brought into a cell by endocytosis. After a vesicle containing food particles fuses with a lysosome, H+ ions are transported into the lysosome from the cytosol. This significantly lowers the pH of the lysosome relative to the cytosol and activates the enzymes that digest the particles. Which of the following best predicts what will happen to the lysosomal enzymes if the proteins that transport H+ ions from the cytosol into the lysosome are damaged?

The lysosomal enzymes will not become active, since there will be no active transport of H+H+ ions.

Gaucher disease is an inherited disorder in which cells of the body are unable to break down a particular type of lipid, resulting in a buildup of the lipid in some tissues and organs. Based on the information provided, Gaucher disease results most directly from a defect in the function of which of the following organelles?

The lysosome

Based on the information provided, Gaucher disease results most directly from a defect in the function of which of the following organelles?

The lysosome.

Which of the follow indicates the mean number per cross of F2 plants producing medium-red grain and correctly explains the distribution of the phenotypes?

The mean number of medium-red phenotypes per cross is 20.8. The distribution of phenotypes suggests that multiple genes are involved in grain color determination.

Which of the following is common feature of the illustrated reactions showing the linking of monomers to form macromolecules?

The monomers of the two reactions illustrated are joined by covalent bonds with the production of a water molecule.

Researchers discovered a mutant form of the TYR gene with a deletion of a single guanine nucleotide in the beginning of the coding sequence.

The mutation will change all subsequent amino acids in the TYR protein, leading to nonfunctional TYR protein. Individuals with this mutation will lack melanin in their hair, skin, and eyes and will not tan in response to UV radiation.

Some plant species flower in response to increasing daily temperatures in the spring. Many of these species rely on pollinators that migrate based on changes in day length and the position of the Sun. The current global warming trend is placing new selective pressures on the species involved in these relationships. Which of the following best explains the impact of these new selective pressures on the organisms involved?

The plant species will flower earlier in the spring in response to rising temperatures before the arrival of the pollinators, so seeds will not be produced.

The researchers determined that the East lava flow population is not in Hardy-Weinberg equilibrium. Which of the following best explains why the population is not in Hardy-Weinberg equilibrium?

The presence of MC1Rd alleles in the East lava flow population is an indication of gene flow from mice populations living on light granite rocks.

A certain type of specialized cell contains an unusually large amount of rough endoplasmic reticulum (ER). Which of the following functions is this cell type most likely specialized to perform?

The production and secretion of proteins

Which of the following functions is the cell type most likely specialized to perform?

The production and secretion of proteins.

Which of the following best describes how the ratio of the density of stomata (stomata per mm^2) per CO2 concentration (ppm CO2) changes as the CO2 concentration increases?

The ratio DECREASES from 0.86 to 0.63, because fewer stomata are needed at higher CO2 concentrations.

Which of the following best describes how the ratio of the density of stomata (stomata per mm2) per CO2 concentration (ppm CO2) changes as the CO2 concentration increases?

The ratio decreases from 0.86 to 0.63, because fewer stomata are needed at higher CO2 concentrations.

Stomata are pores on the surfaces of the leaves and stems of plants that regulate gas exchange between the plants and the atmosphere. Researchers found that the stomata density on the leaves of a species of plant change as the concentration of CO2 in the atmosphere changes. When grown at 350 ppm CO2 the plant has an average density of 300 stomata per mm2, but when grown at 400 ppm CO2 the plant has an average density of 250 stomata per mm2. Which of the following best describes how the ratio of the density of stomata (stomata per mm2) per CO2 concentration (ppm CO2) changes as the CO2 concentration increases?

The ratio increases from 0.630.63 to 0.860.86, because more stomata are needed at higher CO2CO2 concentrations.

Hereditary spherocytosis (HS) is a disorder of red blood cells that causes the cells to be smaller and spherical instead of having the usual flattened, biconcave shape. The average diameter of normal red blood cells is 7.2μm, and the average diameter of red blood cells in a person with HS was found to be 6.7μm. The normal red blood cell has an average surface area of 136μm2 and an average volume of 91μm3. Which of the following provides an accurate calculation of the surface area to volume ratio of an HS red blood cell, as well as a prediction of its effect on the efficient transferring of oxygen compared to a normal red blood cell?

The ratio is 0.89, and the cells are less efficient at transferring oxygen.

The ratio is 1.121.12, and the cells are less efficient at transferring oxygen.

P area on ribosome

The ribosomal site most frequently occupied by peptidyl-tRNA, the tRNA carrying the growing peptide chain. Polypeptide

A scientist is studying the various prokaryotic and eukaryotic species found floating in a sample of water taken from a marine ecosystem. Which cellular component will be found in the widest range of organisms in the sample?

The ribosome, since all organisms need to synthesize proteins.

Which cellular component will be found in the widest range of organisms in the sample?

The ribosome, since all organisms need to synthesize proteins.

The total system that includes photosynthetic organisms and the sun becomes less ordered overtime.

A scientist maintains a large population of the fruit fly Drosophila affinis in the laboratory. After 20 generations of allowing this population of about 1000 flies to mate randomly, 10 females and 10 males were isolated from the rest of the population. Both the larger population and the isolated population were maintained under identical conditions and allowed to mate randomly for another 20 generations. After the 20 generations, DNA sequencing was used to determine the genetic composition of each population. Which of the following predicts the expected outcome of the experiment?

The two populations will show significant genetic differences because the founder effect will result in significant losses in diversity in the smaller population.

Which of the following statements provides reasoning that supports the claim that brown fatty tissue keeps an animal warm?

The uncoupling protein in this tissue reduces the proton gradient across the membrane in this produces heat to warm the animal without ATP production.

Researchers conducted an experiment to investigate the effects of a valinomycin treatment on skeletal muscle cells. Valinomycin is a naturally occurring substance that can be used as a drug. The results of the experiment are presented in the table. Relative Rates of ATP ProductionTime after TreatmentUntreated CellsValinomycin-Treated Cells5 minutes1.00.310 minutes7.72.7 Which of the following claims about the effects of the valinomycin treatment is best supported by the data presented in the table?

The valinomycin treatment caused a decrease in the activity of the mitochondria.

Which of the following claims about the effects of the valinomycin treatment is best supported by the data presented in the table?

The valinomycin treatment caused a decrease in the activity of the mitochondria.

layer of ice 0 degree C, air -5 degree C, water 4 degree C best describes how the structure of ice benefits the organisms that live in the water below?

The water molecules in ice are farther apart than those in liquid water, so the ice floats, maintaining the warmer, denser water at the lake bottom.

One of the main points of those who oppose GM foods is A. insect-resistant GM plants require less insecticide, reducing chemicals that enter food products. B. the cost of agriculture decreases with an increased use of GM crops. C. there have not been any long-term studies done about possible health hazards of GM foods. D. the overall crop yield increases when GM foods are grown.

There have not been any long-term studies done about possible health hazards of GM foods

Iridium is an element that is rare on Earth but commonly found in meteorites. A scientist believes that the first organic molecules may have come to Earth on meteorites 3.6 billion years ago. Which of these would be an appropriate null hypothesis to test related to whether meteorites hit the Earth 3.6 billion years ago?

There is no difference in iridium levels in sediments that were deposited on Earth 3.6 billion years old, compared to recent sediments.

Which of the following statements best describes a primary function of plasmodesmata?

They allow the movement of molecules from one cell to another, enabling communication between cells.

Which statement is not true about structural isomers?

They are a result of restricted movement around a carbon double bond.

What is not a simarity between the nucleus, cholorplast,mitochondria

They are all derived from the ER system

Which would be the best method for reducing acid precipitation?

Tighten emission control standards for factories and automobiles.

All of the following are goals of genetic modification except A. to produce more nutritious foods. B. to produce smaller food products. C. to create less expensive foods. D. to create less harmful manufacturing processes.

To produce smaller food products

What term defines Mendel's plants that self-pollinated and produced identical successive generations? A. True-breeding B. Genetic C. F1 cross D. Cross-pollinated

True-breeding

Sex chromosome disorders include A. Klinefelter's syndrome and cystic fibrosis. B. Turner's syndrome and sickle cell disease. C. Turner's syndrome and Klinefelter's syndrome. D. cystic fibrosis and sickle cell disease.

Turner's Syndrome and Klinefelter's syndrome

Figure 1. Model of damage to DNA caused by UV exposure Which of the following statements best explains what is shown in Figure 1 ?

UV photons cause dimers to form, leading to misshapen DNA, which results in replication and transcription errors.

What additional procedure would best help determine whether these movements are due to active transport or passive transport?

Use two additional treatments, one containing only ethyl alcohol and one containing only acetate. Include a substance known to block ATP use by the plasma membrane. Compare the graphs of these two treatments to the original graph.

What additional procedure would best help determine whether these movements are due to active transport or to passive transport?

Certain bacteria can use both ethyl alcohol and acetate as sources of nutrients. In an experiment where both nutrients are available to a bacterial population, the following results were obtained and graphed. What additional procedure would best help determine whether these movements are due to active transport or to passive transport?

Use two additional treatments, one containing only ethyl alcohol and one containing only acetate. Include a substance known to block ATPATP use by the plasma membrane. Compare the graphs of these two treatments to the original graph.

Which of the following results best refutes the alternative hypothesis that selective permeability is a consequence of the cell wall?

When beetroot cells are placed in a solution with cellulase, the solution remains clear.

Which of the following pieces of evidence would best support the researchers' claim above?

When researchers applied a drug that activates adenylyl cyclase to the mutant mice's ears, the level of melanin increased.

Which of the following best supports the claim that binding of miRNA‑delta to the miRNA binding site inhibits translation of gene Q mRNA?

When the miRNA binding site sequence is altered, translation of Q mRNA occurs in the presence of miRNA-delta.

What sex chromosome pair is present in human males? A. YY B. XY C. YZ D. XX

What chromosome would not carry genes that are absolutely necessary for survival? A. Y chromosome B. X chromosome C. Autosome D. Genome

Y chromosome

How do antibodies work?

Y shaped protein each with a slightly different pocket on tip, when matches a birus, they bump into each other and leads to destruction

A researcher claims that budding used are able to survive in different environments because they produce enzymes that allow them to use different molecules as sources of matter and energy. Which of the following statements best helps justify the researchers claim by providing a relevant example?

Yeast cells produce INVERTASE, which is an enzyme that catalyzes the conversion of the disaccharide sucrose into glucose and fructose.

Yeast cells produce invertase, which is an enzyme that catalyzes the conversion of the disaccharide sucrose into glucose and fructose.

In the past century, the average temperature of the oceans has increased by 0.74 degrees C. Is this evidence of global warming?

Yes, because of the high specific heat of water and the huge volume of water in the oceans, a small rise in temperature would reflect a large amount of heat absorbed by the oceans.

Based on the data, scientists claim that the reproductive behavior of European flycatchers is influenced by the availability of energy sources. Which of the following statements best justifies this claim?

Young European flycatchers hatch from eggs when caterpillar biomass is available for the young birds to consume and convert into energy for growth.

The cell membranes of Antarctic ice fish might have which of the following adaptations?

a high percentage of polyunsaturated fatty acids

The partial negative charge at one end of a water molecule is attracted to a partial positive charge of another water molecule. What is this type of attraction called?

a hydrogen bond

The dotted line in the figure above indicates ____.

a hydrogen bond (thats not the real pic btw)

What is an analogy?

a similarity between organisms that is due to convergent evolution, not ancestry

hermaphrodites

a single individual that can produce both sperm and ova, do not have to find right mate, everyone is potential partner

The cells of an ant and an elephant are, on average, the same size; an elephant just has more cells. What is the main advantage of small cell size?

a small cell has a smaller cytoplasmic volume relative to its surface area, which helps to ensure the exchange of sufficient materials across the plasma membrane

B pleated sheets are characterized by

folds stabilized by hydrogen bonds between segments of the polypeptide backbone.

Where do the catabolic products of fatty acid breakdown enter into the citric acid cycle?

acetyl CoA

Which of the following intermediary metabolites enters the citric acid cycle and is formed, in part, by the removal of a carbon (CO2) from one molecule of pyruvate?

acetyl CoA

A student is using dialysis bags to model the effects of changing solute concentrations on cells. The student places one dialysis bag that contains 25 mL of distilled water into each of two beakers that are filled with 200 mL of distilled water. (Figure 1). The membrane of each dialysis bag membrane contains pores that allow small solutes such as monoatomic ions to pass through but are too small for anything larger to pass. After 30 minutes, 5 mL of a concentrated solution of albumin (a medium-sized, water-soluble protein) is added to one of the two beakers. Nothing is added to the other beaker. After two more hours at room temperature, the mass of each bag is determined. There is no change in the mass of the dialysis bag in the beaker to which no albumin was added. Which of the graphs below best represents the predicted change in mass over time of the dialysis bag in the beaker to which albumin was added?

albumin added goes down decreased heavily

Why does the body not cause an autoimmune reaction?

antigen receptors are randomly arranged some immature lymphocytes produce receptors spec for epitopes on orgs own molecule as lymph mature, the receptors are tested for self react...if yes, apop.

Temperature is a measure of

average kinetic energy of molecules.

What is a chromatid?

b) a replicate chromosome

Some regions of the plasma membrane, called lipid rafts, have a higher concentration of cholesterol molecules. At high temperatures, these regions

are less fluid than the surrounding membrane.

Mitochondria

are often more numerous near areas of major cellular actvity

Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?

as a disaccharide

A major group of G-protein-coupled receptors contains seven transmembrane α helices. The amino end of the protein lies at the exterior of the plasma membrane. Loops of amino acids connect the helices either at the exterior face or on the cytosol face of the membrane. The loop on the cytosol side between helices 5 and 6 is usually substantially longer than the others. The coupled G protein most likely interacts with this receptor

at the loop between H5 and H6

Several members of a family are found to involuntarily sneeze when exposed to bright lights, such as sunlight. Following analysis of the condition in the family, a doctor predicts that the symptoms have an underlying genetic basis. A pedigree of the family is shown in Figure 1. Figure 1. Pedigree showing family members with and without symptoms For this condition, which of the following modes of inheritance is most consistent with the observations?

autosomal dominant

Living organisms must gather energy and materials from their surroundings to __.

build new biochemicals grow maintain and repair their parts produce offspring (e. all of the above)

Movement of urine through the urinary tract

bulk flow

Polytomy-

branch point from which two or more descendant groups emerge

Muscle Tissues-

body movement and contraction skeletal- (striated, striped)..voluntary movement, mult nucleii (bending finger) smooth- not striated, involuntary movement (peristalsis) cardiac (striated) interrelated disks, interconnect all cells, rhythmic movemtn (contractile wall of heart)

Human metabolic activities- daily cycles:

body temp, cyclic rise and fall of 6 celsius every 24 hours...jet lag affects

hydra exchange materials-

body wall= two layers thick, outside and inside layers are constantly in contact with the environment

If cells are grown in a medium containing radioactive 32P-labeled phosphate, which of these molecules will be labeled?

both phospholipids and nucleic acids

In photosynthetic cells, synthesis of ATP by the chemiosmotic mechanism occurs during

both photosynthesis and respiration.

WHat changes...for homeostasis, when climbing mountain

breathe heavier...more CO2 released pH changes... alkaline urine

Which of the following is not a trace element in the human body?

calcium

Compared to C3 plants, C4 plants

can continue to fix CO2 even at relatively low CO2 concentrations and high oxygen concentrations.

effect of locations and types of mutations on proteins // point mutation

can have significant impact on phenotype // point mutations in noncoding regions are generally harmless or cause improvement

In the thylakoid membranes, what is the main role of the pigment molecules in a light-harvesting complex?

capture light energy to release electrons from Magnesium

cooling the hypothalamus

causes body temperature to rise by constricting blood vessels to the skin or increasing metabolic rate

Specific Defenses-

cell mediated and humoral (look at sheet)

endocrine pathway-

cells respond to change in internal or external stimulus, secretes hormones, trigger response to target cells... ex: pH in duodenum, (sm intestine), very acidic, as contents enter, ther low pH stimulates cell to secret secretin...which diffuses into blood and each target in pancrease....release to neutralia

Which of the following is NOT a logical hierarchy of biological organization?

cells, molecules, organelles, tissues, systems

On food packages, to what does the term insoluble fiber refer?

cellulose

Which organelle or structure is absent in plant cells?

centrosomes

Polypeptides

chains of amino acids, linked by peptide bonds

Positive Feedback example-

child birth, pressure of babys head stimulates uterus to contract...increases, baby is born

Another way to distinguish between homology and analogy-

chimp and human skull gene level, if genes in two orgs share many portions of nucleotide seq,..likely homologous. more elements similar in complex structures, ,C.A. analogous

All of the following contain amino acids except

cholesterol.

To monitor the rate of cellular respiration, you might use a microrespirometer (as we discussed in class). This method is dependent on a cotton ball soaked in KOH to:

convert created CO2 gas to a solid

Polymerization (the formation of polymers) is a process that

creates bonds between amino acids in the formation of a polypeptide, involves the removal of a water molecule, links the sugar of one nucleotide with the phosphate of the next, and involves a dehydration reaction.

Which of the following are nitrogenous bases of the pyrimidine type?

cytosine and uracil

Polymers of carbohydrates and proteins are all synthesized from monomers by which of the following processes?

dehydration reactions

What is the chemical reaction mechanism by which cells make polymers from monomers?

dehydration reactions

Reactions that remove the equivalent of a water molecule when subunits are joined to make a large molecule are called ___ reactions.

dehydration synthesis

error signal

difference between set point and feedback

There are 20 different amino acids. What makes one amino acid different from another?

different side chains (R groups) attached to an α carbon

Major Lipid Soluble-

diffuse across membrane outside, bind to transport proteins leave the blood and diffuse into target cells...bind to recpetors in cytoplasm or nucleus hormone bound receptors trigger change in gene transcription

The movement of the hydrophobic gas nitrous oxide (N2O) (laughing gas) into a cell is an example of

diffusion across the lipid bilayer

Conduction-

direct transfer of thermal motion between moecules of object in contact with each other (lizard on hot rock)

Another issue with tree system

distinguishes mammals, amphibians and reptiles, but tells nothing of their evolutionary relations

The Golgi apparatus has a polarity or sidedness to its structure and function. Which of the following statements correctly describes this polarity? a) Proteins in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. b) Soluble proteins in the cisternae (interior) of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. c) Transport vesicles fuse with one side of the Golgi and leave from the opposite side. d) Lipids in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. e) All of the above correctly describe polar characteristics of the Golgi function.

e) All of the above correctly describe polar characteristics of the Golgi function.

Radiation-

emission of EM waves by all objects warmer thatn absolute 0. Absorb sun and radiates E to air.

Transmission Endo vs. Ner

endo- cells with receptors nerv- axons

membranes euks vs pros

euks- cells walls are chitin and cellulose pros- peptidoglycan capsule of polysacch and pro

Why are there mistakes between the tree and taxonomy?

ex: taxonomy placed species in a genus where it's not most closely related reason: over course of evolution, a species lost a key feature shared by relatives (DNA reveals this and org is reclassified)

Glucose diffuses slowly through artificial phospholipid bilayers. The cells lining the small intestine, however, rapidly move large quantities of glucose from the glucose-rich food into their glucose-poor cytoplasm. Using this information, which transport mechanism is most probably functioning in the intestinal cells?

facilitated diffusion

Which of the following molecules provides the most energy (kcal/g) when eaten and digested?

fat

Insulation-

fat, fur....goosebumps are from when we had hair, insulated "air" layer

What are trans fats?

fats that contain trans double bonds may contribute to atherosclerosis

The mechanism in which the end product of a metabolic pathway inhibits an earlier step in the pathway is most precisely described as

feedback inhibition.

Why are Archaea equally related to Bacteria and Eukarya?

first major split was when bacteria diverged...if true, arch and euk are more closely related recent findings say that euks share more recent CA with bacteria

tape worm exchange materials-

flat shape, reach several meters, most cells- direct contact with environment

Epithetlial tissue function and location-

function- cover body and line organs, serves as barrier ag pathogens and fluid loss locations- nasal passage, kidneys, glands, intestines, skin, respt tract, anus, mouth, vagina ex: squamous, flat short thin, leaky, exchange by diffusion (lin of blood vessels or air sacs in lungs) cuboidal- dice shaped, secretion, (glands, kidney tubules) columnar- tall large, secretion and absorption, (linings of intestines)

The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are in the α form. Which of the following could amylase break down?

glycogen, starch, and amylopectin

Which process in eukaryotic cells will proceed normally whether oxygen (O2) is present or absent?

glycolysis

Which catabolic processes may have been used by cells on ancient Earth before free oxygen became available?

glycolysis and fermentation only

cola-2; orange juice-3; beer-4; coffee-5; human blood-7.4 Which of these liquids has the highest molar concentration of OH-?

human blood

Humans can digest starch but not cellulose because

humans have enzymes that can hydrolyze the glycosidic linkages of starch but not the glycosidic linkages of cellulose.

the fats stored in your body consist mostly of

hydrocarbons

The two strands of a DNA double helix are held to each other by ___ bonds between nitrogenous bases.

hydrogen

The bonds that are broken when water vaporizes are

hydrogen bonds between water molecules.

which of the following statements about evolution is false?

individuals evolve

Non-specific internal defenses-

inflammatory response- second line, mast cells produce histamine...when something not self, search for invaders, bring WBCs to area (fluid) cellular innate defenses- leukocytes, phagocytes---macrophages are big eaters, guards that don't travel natural killer cells--recognize absense of MHC and kills other human cells dendritic--"bridge",, WBC that stimulates nect line of defense engulf, with lysosome and display part on outside

positive feedback

information that amplifies a regulatory response, increasing the deviation of the system from the set point

negative feedback

information that decreases a regulatory response, returning the system to set point

Natural selection on a trait can only occur if the trait is

inheritable

The extracellular matrix is thought to participate in the regulation of animal cell behavior by communicating information from the outside to the inside of the cell via which of the following?

integrins

The tremendous variation and unique properties of proteins are most likely a result of

interactions between R groups of the amino acids

A triple covalent bond would

involve the sharing of six electrons.

Lysosomes are

involved in the deflation of cellular substances

Euglenids are single-cell eukaryotes that live in aquatic environments. The chloroplasts found inside euglenids are enveloped by three membranes, as represented in Figure 1. The inner membrane of euglenid chloroplasts resembles the thylakoid membrane. Figure 1. Simplified diagram of a euglenid, showing the structure of the chloroplast envelope Which of the following claims about the origin of the euglenid chloroplast is best supported by the three-membrane structure of the envelope?

it originated from the incorporation of a photosynthetic prokaryote into a eukaryotic cell by two endosymbiotic events.

A cow can derive nutrient from cellulose because

its rumen contains prokaryotes that can hydrolyze the bonds of cellulose.

cholesterol

lipid

triacylglycerol

lipid

punctuated equilibrium

long periods of apparent stasis, in which species undergoes little or no morphological change, interrupted by relatively brief periods of sudden change

The differences among the three categories of cytoskeletal elements outlined in the table above would suggest that each of the following has specialized roles. Which of the following is a correct match? (All three elements are involved in the maintenance of cell shape.)

microtubules and chromosome movement

Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic cells?

mitochondrial intermembrane space

Which structure is common to plant and animal cells?

mitochondrion

The ability of morphine to mimic the effect of the body's endorphins is due to

molecular shape similarities that allow morphine to bind to endorphin receptors.

Answer to previous question:

monosaccharide

effect of locations and types of mutations on proteins // frameshift mutation (insertion & deletion)

most harmful mutation

Nervous System-

networks of specialized cells transmit signals along certain pathways signals regulate, nerons, muscle cells and endocrine cells (regulate release of hormones)

synaptic pathway:

neurotransmitters diffuse across synapses and trigger resp in cells of target tissues ex: neuron to muscle, contraction

Isotopes of the same element differ from each other in the number of

neutrons only

Why do bacteria evolve much faster than multicellular euks?

new mutations are rare, but can increase genetic dicersity wuickly due to short generation times and large populations adapt wuickly

The chemical bonds that are formed when atoms share electrons equally are called ___.

nonpolar covalent bonds

location of receptors for hormones

on the cell's surface (peptide and protein, amine) or inside the cell (steroids and some amine hormones)

The chemical reactions involved in respiration are virtually identical between prokaryotic and eukaryotic cells. In eukaryotic cells, ATP is synthesized primarily on the inner membrane of the mitochondria. In light of the endosymbiont theory for the evolutionary origin of mitochondria, where is most ATP synthesis likely to occur in prokaryotic cells?

on the plasma membrane

12/6 C, 16/8 O, 1/1 H, 14/7 N, 32/16 S, 31/15 P How many of the elements listed on the previous page are found next to each other (side by side) on the periodic table?

one group of 2 and one group of 3.

Compared with 31P, the radioactive isotope 32P has

one more neutron.

cola-2; orange juice-3; beer-4; coffee-5; human blood-7.4 Comparing the [H+] of orange juice and coffee, the [H+] of

orange juice is 100 times higher.

In general, molecules made mostly of carbon atoms covalently bound to each other and to other atoms are called ___.

organic molecules

Hypothalamus-

part of brain aboce roof of mouth, acts as a thermostat...increase, on sweat or vasilodil...decrease, off, goosebumps vasioconstrivtion

Why do antibiotics only affect bacteria cells and not euks?

peptidoglycan makes drugs able to penetrate cell walls prokary ribo are much smaller, and differ in pro and RNA...bind to ribosome and block protein synthesis

adaptive radiation

period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles in their communities

The physical characteristics of an organism are called its ____________, whereas the genetic characteristics of an organism are called its ____________. A. genotype; phenotype B. phenotype; genotype C. heredity; genotype D. alleles; phenotype

phenotype; genotype

All of the following serve an important role in determining or maintaining the structure of plant cells. Which of the following are distinct from the others in their composition?

plant cell walls

growth and reg in plants and animals-

plants- hormones, control growth pattern..flower animals- homeostatic development

Env Resp in Plants vs Animals

plants- photoreceptors, detect light animals- pathways

hybrid breakdown

postzygotic barrier // first generation hybrids are viable and fertile, but when they mate with one another or with the parental species the offspring of the next generation are feeble and may even be sterile

reduced hybrid variability

postzygotic barrier // genes of different parent species may interact and impair hybrid's development

reduces hybrid fertility

postzygotic barrier // hybrids may be sterile, if chromosomes of two parent species differ in number or structure meiosis in hybrids may fail to produce normal gametes, if infertile hybrids can't produce offspring then genes can't flow freely between species

behavioral isolation

prezygotic mechanism // courtship rituals that attract mates other behaviors unique to a species are effective reproductive barriers, even between closely related species

temporal isolation

prezygotic mechanism // species that breed at different times of day, seasons, or years can't mix gametes

habitat isolation

prezygotic mechanism // two species that occupy different habitats within the same area may encounter each other rarely, even though not isolated by physcical barriers

The unique sequence of monomer subunits in a protein is the ___ structure of the protein.

primary

If cells are grown in a medium containing radioactive 35S, which of these molecules will be labeled?

proteins

Which of the following types of molecules are the most diverse in terms of structure and types of roles in cells?

proteins

Which of the macromolecules below could be structural parts of the cell, enzymes, or involved in cell movement or communication?

proteins

Adding a base to a solution would

raise the pH and decrease [H+].

The NADPH required for the Calvin cycle comes from

reactions initiated in photosystem I.

Nervous Tissues

reception processing and transmission of info, in the brain glia support nerve cells, nourish replenish and insulate neurons

Regulators vs. Conformers-

regulator- internal mechanism is used to control internal change conformer- intern conditions changes with environment

Major Water Soluble-

secreted by exocytosis travel freely can't diffuse through plasma membrane bind to cell surface receptors cause changes in cytoplasmic molecules and gene transcription

The principle of maximum parsimony-

simplest explanations, consistent with the facts measured by origin of shared derived morph char fewest base changes

Non-specific external barriers-

skin- first line defense, pathogens out, oily, acidic mucuos membrane- line all internal surfaces, viscous fluid, sweeps pathogens away low pH in stomach- hostile, outside body, selected for, pH is 2

A trace element is one found in specific organisms in ___ quantities and is ___ for normal biological functions.

small vital

epitopes (antigenic determinants)

small portions of non-self substances

What is interstitial fluid and how does it aid with exchange of materials?

spaces between cells are filled with this fluid exchange between intersitial fluid and circulatory fluid enables cells in body to obtain nutrients and get rid of waste

Claudes-

species placed in groups where have ancestral species and all descendants

Outgroup-

species/group from evol lineage known to have diverged before the lineage that lineage that includes species being studied

hypothalamus

specific brain location of major integrative center of the vertebrate thermostate

The a helix proteins is

stabilized by hydrogen bonds and is commonly found in fibrous proteins.

What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division?

standard light microscopy

How is it determined where a shared char first evolved?

suitable outgroup can be deter based on evidence, morphology, paleantology.. compare members of ingroup with each other ex: backbones in vertegrates

12/6 C, 16/8 O, 1/1 H, 14/7 N, 32/16 S, 31/15 P Based on electron configuration, which of the following elements would have chemical behavior most like that of oxygen?

sulfur

metabolic rate-

sum of all the energy (calories) and organism uses in a unit of time

Most cells cannot harness heat to perform work because

temperature is usually uniform throughout a cell.

advantage of sexual reproduction over asexual reproduction

the generation of genetic diversity

The ___ structure of a protein refers to the conformation, or overall three-dimensional shape, of a polypeptide that has been folded into a functional protein

tertiary

What is the molecular shape of methane (CH4)?

tetrahedral, due to the hybridiation of the s and three p orbitals of carbon.

Hydrocarbons are not soluble in water because

the C-H bond is non-polar

Some of Darwin's most important discoveries were based on studies of birds captured in

the Galapagos Islands

In the term trace element, the adjective trace means that

the element is required in very small amounts.

What is phylogeny?

the evolutionary history of a species or group of species used to organize biodiversity sorted based on data: fossils, genes, biological molecules

The reactivity of an atom arises from

the existence of unpaired electrons in the valence shell.

In a reaction in chemical equilibrium,

the forward and reverse reaction are occurring at the same rate.

You have three flasks containing 100mL of different liquids. Each is warmed with 100 calories of heat. The temperature of the liquid in flask 1 rises 1 degree C; in flask 2 it rises 1.5 degrees C; and in flask 3 it rises 2 degrees C. Which of these liquids has the highest specific heat?

the liquid in flask 1

Which of the following is a major cause of the size limits for certain types of cells?

the need for sufficient surface area to support the cell's metabolic needs

The molarity of a solution is equal to

the number of moles of a solute in 1 liter of solution

Which action could produce a carbonyl group?

the replacement of the --OH of a carboxyl group with hydrogen

The laws of chemistry and physics that govern living things are ___ the laws of chemistry and physics that govern nonliving things.

the same as

What determines the sequence of the amino acids in a particular protein?

the sequence of nucleotides in RNA, which was determined by the sequence of nucleotides in the gene for that protein.

In mitochondria, chemiosmosis (via proton pumps) translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from

the stroma to the thylakoid space.

Organic chemistry is currently defined as

the study of carbon compounds

Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes?

the synthesis of ATP

Based on your understanding of enzyme structure, which of the following would you recommend that they also investigate?

the temperature of the liquid in the washing vat

A covalent bond between two atoms is likely to be non-polar if

the two atoms are about equally electronegative and the two atoms are of the same element.

Some bacteria are metabolically active in hot springs because

their enzymes have high optimal temperatures.

Why are archaea placed in their own domain of life?

they have characteristics from euks and pros aren't classified or necessarily more related to one or the other

if the dipeptide in the figure were to be digested, how would it be reduced to amino acids?

through a hydroysis reaction in which water is added.

FLuid Connective Tissue-

tissues with liquid matrix, functional connection Blood- erythrocytes (red), leukocytes (white) plasma is liqui matrix lymph- intersitial spaces,

The primary function of polysaccharides attached to the glycoproteins and glycolipids of animal cell membranes is

to mediate cell-to-cell recognition

Purpose of Immune System-

to recognize and neautralize potentially harmful substances

In a liver cell detoxifying alcohol and some other poisons, the enzymes of the peroxisome remove hydrogen from these molecules and

transfer the hydrogen to oxygen molecules to generate hydrogen peroxide

Cells require which of the following to form cilia or flagella?

tubulin

In animal metabolism, most of the monomers released by digestion of food macromolecules are metabolized to provide energy. Only a small portion of these monomers are used for synthesis of new macromolecules. The net result is that

water is consumed by animal metabolism.

ability of hormones to bind to variety of cells

water soluble, peptide and protein easily go through blood

when the concentration of solutes differs on the two sides of a membrane permeable only to water

water will move across the membrane via osmosis

"Negative feedback loops are common to all regulatory pathways in the body."

way to conserve E simple by decreasing hormone signaling, neg feedback reg precents excess activity

endocrine system

what parts of the body secrete hormones (cells scattered in organs or endocrine glands)

Insertion

Addition of one letter to DNA sequence

Repressible operon

An operon whose transcription is reduced in the presence of a particular substance, often the end product of a biosynthetic pathway. Tryptophan

Eukaryote gene expression

Control strategies maintain homeostasis and drive development

what determines which traits will be passed on to the next generation in the greatest frequency?

D) the fit of the trait to the environment

5' to 3'

DNA strand runs from

Alternative gene splicing

Different RNA molecules are produced from the same primary transcript

a small population is likely to evolve because of₋₋₋, but this not likely to be true for large populations

Genetic drifts in a small population, mutation, natural selection, A,B,C are correct

RNA polymerase

Initiation begins with ___ recognizes and binds to DNA at the promoter region, must have access and capable of binding to promoter for transcription to begin

Euchromatin

Is a lightly packed form of chromatin that is enriched in genes, and is often under active transcription

DNA ligase

Joins DNA fragments together

Prokaryote gene expression

Need to respond quickly to changes in environment, metabolism- turns genes on and off quickly, control strategies geared to adjust to environmental changes

Amino acids

Present in cytoplasm and carried by tRNA molecules to codons of mRNA strand at the ribosome

Poly-A tail polypeptide, attached to 3'

Protects mRNA from exonucleases

3' to 5'

RNA polymerase reads DNA from

Most commercial pesticides are effective for only 2-3 years. this is because

Those pests with advantageous mutations will survive and reproduce

in many species of fireflies males flash to attract females. Each species has a different flashing pattern. this is an example of

behavioral isolation

Inducible

Type of operon Lac

The human appendix which has no known function today is an example of a(n)

Vestigial structure

Methylation

___ of certain bases to DNA silences that DNA temporarily or for long periods of time. Or by removing them genes are turned on

which of the following "species" cannot be tested via the biological species concept to see if all the individual organisms are in fact a single species

a dinosaur species

A bacterial allele that conveys resistance to the antibiotic streptomycin

is beneficial to the cell in the presence of streptomycin

The great dane and the chhihuahua are both domestic dogs (the same species), but mating between them is limited by

mechanical incompatibility

Equilibrium actually means

no charge in allele frequency

which of the following categories is the smallest capable of evolution

population

imagine a population of frogs in a tropical rain forest whose habitat has been reduced to the point where only 25 frogs survive. this is an example of

population bottlenecks

set point

posted speed limit

feedback information

reading on speedometer

Elongation of translation

tRNA brings amino acids to the ribosome and a polypeptide chain is formed

two different species of pine release their pollen at different times. this is an example of

temporal isolation

brown fat

uncouples oxidative phosphorylation from ATP production, releasing heat for non-shivering thermogenesis

Convergent evolution occurs when

unrelated organisms develop analogous structures.

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Which statement about receptors and enzymes is true?

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mis 3 par

MGMT 450 CH 2

Chapter 4 LearnSmart

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