Biology Final

During a lab experiment, you discover that an enzyme-catalyzed reaction has a deltaG of -20 kcal/mol. If you double the amount of enzyme in the reaction, what will be the deltaG for the new reaction?

-20 kcal/mol

During a laboratory experiment, you discover that an enzyme- catalyzed reaction has a delta G of -20 kcal/mol. If you double the amount of enzyme in the reaction, what will be the delta G for the new reaction?

-20 kcal/mol

When an ionic compound such as sodium chloride (NaCl) is placed in water, the component atoms of the NaCl crystal dissociate into individual sodium ions and chloride ions. In contrast, the atoms of covalently bonded molecules (glucose, sucrose, glycerol) do not generally dissociate when placed in aqueous solution. Which of the following solutions would be expected to contain the greatest number of solute particles (molecules or ions)?

1 liter of 1.0 M NaCl

chromosomes in one gamete

23

A particular triplet of bases in the Template strand of DNA is 5' AGT 3'... corresponding codon for mRNA is?

3' UCA 5'

chromosomes in somatic cells

46

Klinefelter syndrome

A chromosomal disorder in which males have an extra X chromosome, making them XXY instead of XY.

Zinc, an essential trace element for most organisms, is present in the active site of the enzyme carboxypeptidase. The zinc most likely functions as ____.

A cofactor necessary for enzyme activity

A glycosidic linkage is analogous to which of the following in proteins?

A peptide bond

Which of the following Occurs in eukaryotic gene expression but not in prokaryotic?

A poly-A tail is added to 3' end of mRNA and cap added to 5' end

Which of the following effects can occur because of the high surface tension of water?

A raft spider can walk across the surface of a small pond

A protein that spans the phospholipid bilayer one or more times is

A transmembrane protein

Supposing you undertook an experiment to Analyze nucleotide composition of DNA, which of the following would you expect to find?

A+C = G+T

chargaff's rules

A=T & C=G

In the formation of biofilms, such as those forming on unbrushed teeth, cell signaling serves which function?

Aggregation of bacteria that can cause cavities

Altering patterns of gene expression in prokaryotes would most likely serve an organism's survival by ___?

Allowing organism to adjust to changes in environmental conditions

In response to chemical signals, prokaryotes can do which of the following?

Alter the level of production of various enzymes

Which kind of metabolic poison would most directly interfere with glycolysis?

An agent that closely mimics the structure of glucose but is not metabolized

Living organisms increase in complexity as they grow, resulting in a decrease in the entropy of an organism. How does this relate to the second law of thermodynamics?

As a consequence of growing, organisms cause a greater increase in entropy in their environment than the decrease in entropy associated with their growth.

Prokaryotes are classified as belonging to two different domains. What are the domains?

Bacteria and archaea

Myah wants to clone a relatively long sequence of DNA of ~200 kb. Which vector should she use?

Bacterial artificial chromosome (BAC)

The Role of a metabolite that controls repressible operon is to?

Bind to repressor protein and activate it

Testosterone function inside a cell by ___?

Binding with a receptor protein that enters the nucleus and activates specific genes

Which of the following Involves metabolic cooperation among prokaryotic cells?

Biofilms

Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on specificity in the

Bonding of the anticodon to the codon and the attachment of amino acids to tRNA

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

Which of the listed statements describes the results of the following reaction? C6H12O6+6O2 -> 6CO2 + 6H2o+ energy

C6H12O6 is oxidized and O2 is reduced

A system at chemical equilibrium _____.

Can do no work

Tumor-suppressor genes ___?

Can encode proteins that promote DNA repair or cell-cell adhesion

About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter?

Carbon, hydrogen, nitrogen, oxygen (CHNO)

Which two functional groups are always found in amino acids?

Carboxyl and amino groups

In autumn, the leaves of deciduous trees change colors. This is because chlorophyll is degraded and ____.

Carotenoids and other pigments are still present in the leaves

A cell has enough available ATP to meet its needs for about 30 seconds. What is likely to happen when an athlete exhausts his or her ATP supply?

Catabolic processes are activated that generate more ATP

Which Statement about bacterial cell walls is false?

Cell walls prevent cells from dying in hypertonic conditions

A noncompetitive inhibitor decreases the rate of an enzymatic reaction by ____.

Changing the shape of the enzymes active site

The centromere is a region in which

Chromatids remain attached to one another until anaphase

Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures?

Components of the cytoskeleton

Anabolic pathways _____.

Consume energy to build up polymers from monomers

Assume that you are trying to insert a gene into a plasmid and you have genomic DNA that has been cut with restriction enzyme X... You have a plasmid with a single site for Y, but not for X. You need to?

Cut the DNA again with restriction enzyme Y and insert the fragments into the plasmid cut with the enzyme

plasmid

DNA fragment independent of chromosome

What considerations did Hershey and Chase have in mind in designing their experiment to determine DNA or protein is genetic material?

DNA has phosphorus, protein doesn't

A biochemist isolates, purifies, and combines in a test tube a variety of molecules needed for DNA replication. When she adds some DNA to the mixture, replication occurs, but each DNA molecule consists of a normal strand paired with numerous, unlinked segments of DNA a few hundred nucleotides long. What has she probably left out of the mixture?

DNA ligase

chromatin

DNA+RNA+protein

Base your answer to the question on the information below and on your knowledge of biology. Jerry completed a series of experiments and found that a protein-digesting enzyme (intestinal protease) functions best when the pH is 8.0 and the temperature is 37 degrees C. During an experiment, he used some of the procedures (A-E) listed below. Which procedure would have the least effect on the rate of protein digestion?

Decreasing the amount of light

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

Dehydration reactions assemble polymers; hydrolysis reactions break polymers apart

The Elongation of leading strand during DNA synthesis

Depends on the action of DNA polymerase

classification of organisms

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Which of the following sets of materials are required by both euk and pro for replication?

Double stranded DNA, four kinds of dNTPs, primers, origins

A chemical reaction that has a positive delta G is correctly described as

Endergonic

At puberty, an adolescent female body changes in both structure and function of several organ systems, primarily under the influence of changing concentrations of estrogens and other steroid hormones. How can one hormone, such as estrogen, mediate so many effects?

Estrogen binds to specific receptors inside many kinds of cells, each of which have different responses to its binding

Muscle cells differ from nerves cells mainly because they?

Express different genes

CAM plants keep stomata closed in the daytime, thus reducing the loss of water. They can do this because they____.

Fix CO2 into organic acids during the night

In Colorectal cancer, several genes must be mutated for a cell to develop into a cancer cell. Which of the following kinds of genes would you expect to be mutated?

Genes involved in control of the cell cycle

A mutation that disrupts the ability of an animal cell to add polysaccharide modifications to proteins would most likely cause defects in its ___.

Golgi apparatus and extracellular matrix

Which of the following are compounds?

H2O, CH4, but not O2

Pharmacogenetics is an increasingly important discipline that uses genetic info to tailor prescription or drug treatments...breast cancer/tumor biopsy, aggressive growth and metastasis. How can this help the physician and patient?

Help them decide whether and what kind of chemotherapy is warranted.

The chemiosmotic hypothesis is an important concept in our understanding of cellular metabolism in general because it explains ___?

How ATP is synthesized by a proton motive force

Which type of bond must be broken for water to vaporize?

Hydrogen bonds

steps of mitosis

I- PMAT-C

A colony of bacteria growing on a culture medium is successfully synthesizing an organic compound. Which procedure would be least likely to have an effect on this synthesis?

Increasing the number of hormone molecules in the colony

The membranes of winter wheat are able to remain fluid when it is extremely cold by ____.

Increasing the percentage of unsaturated phospholipids in the membrane

DNA technology has many Medical applications. Which of the following is not done routinely at present?

Introduction of genetically engineered genes into human gametes

Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by humans and other vertebrates, but not by other organisms such as bacteria or plants?

Iodine

If the cytoplasm of a cell is at pH 7, and the mitochondrial matrix is at pH 8, then the concentration of H ions ____.

Is 10 times higher in the cytoplasm than in the mitochondrial matrix

Which of the following statements describes the euk chromosome?

It consists of a single linear molecule of double-stranded DNA plus proteins

Which of the following would not be true of cDNA produced using human brain tissue as the starting material?

It could be used to create a complete genomic library

Which of the following are qualities of any good scientific hypothesis?

It is testable and falsifiable

Which of the following statements about the DNA in one of your brain cells is true?

It is the same as the DNA in one of your heart cells

When ATP releases some energy, it also releases inorganic phosphate. What immediately happens to the inorganic phosphate in the cell?

It may be used to form a phosphorylated intermediate

What is the function of the nuclear pore complex found in eukaryotes?

It regulates the movement of proteins and RNAs into and out of the nucleus

What is the function of reverse transcriptase in retroviruses?

It uses viral RNA as a template for DNA synthesis

You have a friend who lost 7kg (about 15 pounds) of fat on a regimen of strict diet and exercise. How did the fat leave his body?

It was released as CO2 and H2O

Which of the events listed below occurs in the light reactions of photosynthesis?

Light is absorbed and funneled to reaction-center chlorophyll a

The advantage of light microscopy over electron microscopy is that ___.

Light microscopy allows one to view dynamic processes in living cells

Glycolysis is active when cellular energy levels are ___; The regulatory enzyme, phosphofructokinase, is ___ by ATP.

Low; inhibited

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

Lysosomes

Agrobacterium infects plants and causes them to form tumors. You are asked to determine how long a plant must be exposed to these bacteria to become infected. Which of the following experiments will provide the best data to address that question?

Measure the number of tumors formed on plants, which are exposed to agrobacterium for different lengths of time.

The voltage across a membrane is called the _____?

Membrane potential

Which of the following statements is true of metabolism in its entirety in all organisms?

Metabolism uses all of an organism's resources

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?

Mitochondria

Which structure is common to plant and animal cells?

Mitochondrion

In his Transformation experiments, Griffith observed that ____?

Mixing heat killed pathogenic bacteria with living non pathogenic strain can convert some living into pathogenic.

Molybdenum has an atomic number of 42. Several common isotopes exist, with mass numbers from 92-100. Therefore, which of the following can be true?

Molybdenum atoms can have between 50 and 58 neutrons

A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from ___

Nearly any eukaryotic organism

A Mutation resulting in a stop codon at the wrong spot is called?

Nonsense mutation

After completing their double-helix model, Watson and Crick realized that the DNA molecule could carry an enormous amount of hereditary information in which of the following?

Nucleotide base sequences

How does DNA synthesis along the lagging strand differ from that on the leading strand?

Okazaki fragments, which each grow 5' -> 3', must be joined along the lagging strand

Which cell would be best for studying lysosomes?

Phagocytic white blood cell

The difference between pinocytosis and receptor-mediated endocytosis is that _____.

Pinocytosis is nonselective in the molecules it brings into the cell, whereas receptor-mediated endocytosis offers more selectivity.

In Recombinant DNA methods, the term vector refers to?

Plasmid used to transfer DNA into a living cell

What is the difference between aldose sugar and ketose sugar?

Position of the carbonyl groups

Based on your knowledge of the polarity of water molecules, the solute molecule (in center) depicted here is most likely ___.

Positively charged

One possible use of transgenic plants is in the production of human proteins, such as vaccines. Which of the following is a possible hindrance that must be overcome?

Prevention of transmission of plant allergens to the vaccine recipients

A cell with a predominance of free ribosomes is most likely ___?

Primarily producing proteins in the cytosol

A cell with a predominance of rough endoplasmic reticulum is most likely ____?

Producing large quantities of proteins for secretion

Which of the following frequently imposes a limit on cell size?

Ratios of surface area to volume

Which of the following would be inhibited by a drug that specifically blocks the addition of phosphate groups to proteins?

Receptor tyrosine kinase activity

When a neuron responds to a particular neurotransmitter by opening gated ion channels. The neurotransmitter is serving as which part of the signal pathway?

Signaling molecule

Based on your knowledge of biology, examine the diagram below, which represents a chemical reaction that occurs in the human body, and answer the question below: Substances X and Y are examples of which kind of molecule?

Simple sugar

Which of the following Helps hold DNA strands apart during replication?

Single strand binding proteins

Which is the rarest property of water?

Solid water is less dense than liquid water

You need to represent a molecule to best illustrate the relative sizes of the atoms involved and their interrelationships. Which representation would work best?

Space filling model

What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division?

Standard light microscopy

How does Transcription of the structural genes in an inducible operon occur?

Starts when the pathway's substrate is present

A salamander relies on hydrogen bonding to stick to various surfaces. Therefore, a salamander would have the greatest difficulty clinging to a ___.

Surface of hydrocarbons

A Bacterium derives nutrients from digesting human intestinal contents (food). Humans lacking this bacterium have no reproductive advantage or disadvantage to humans that do have it. Bacterium can be described as which of the following?

Symbiont and commensal

A cell with an extensive area of smooth endoplasmic reticulum is specialized to ___.

Synthesize large quantities of lipids

What does Antiparallel mean?

The 5' to 3' direction of one strand runs counter to the 5' to 3' direction of other strand

When biological membranes are frozen and then fractured, they tend to break along the middle of the bilayer. The best explanation for this is that __?

The hydrophobic interactions that hold the membranes together are weakest at this point

Overton has a genetic abnormality which causes his cells to accumulate and get clogged with very large, complex, undigested lipids. Which cellular organelle must be involved in this condition?

The lysosome

As genetic technology makes testing for a wide variety of genotypes possible, which of the following is likely to be an increasingly troublesome issue?

The need to legislate for the protection of the privacy of genetic information.

In a bacterium, we will find DNA in ___?

The nucleoid

How do phospholipids interact with water molecules?

The polar heads interact with the water; the nonpolar tails do not.

Taxonomy

The scientific study of how living things are classified

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?

The toy microscope magnifies a good deal, but has low resolution and therefore poor quality images

Which of the following molecules is polar? C3H7OH C2H5COOH

They are both polar

Why are yeast cells frequently used as hosts for cloning?

They are euk cells

Which of the following statements describes proto-oncogenes?

They can code for proteins associated with cell growth

According to the fluid mosaic model of cell membranes, which of the following is a true statement about membrane phospholipids?

They can move laterally along the plane of the membrane

RNAi methodology uses double stranded pieces of RNA to trigger a breakdown or blocking of mRNA. For which of the following might it more possibly be useful?

To decrease the production from a harmful gain-of-function mutated gene

Edwards syndrome

Trisomy 18 associated with rocker-bottom feet, low-set ears, heart disease

Suppose you were to separate one of several pieces of chromatin from a eukaryotic (animal) nucleus. It might consist of which of the following?

Two long strands of DNA plus proteins

Differences among organisms are caused by differences in the ___.

Types and relative amounts of organic molecules synthesized by each organism

Which of the following is the best explanation for why vegetable oil is a liquid at room temperature while animal fats are solid?

Vegetable oil has more double bonds than animal fats

You like avocados? Which of the following do you and an avocado tree have in common?

You are both multicellular

transformation

a change in genotype and phenotype due to the assimilation of external DNA by a cell

mendel's law of segregation

a diploid organism passes a randomly selected allele for a trait to its offspring, such that the offspring receives one allele from each parent.

in comparison to eukaryotes, prokaryotes...

are smaller

If new genetic variation in the experimental populations arose solely by spontaneous mutations, then the Most effective process for subsequently increasing the prevalence of beneficial mutations in the population over the course of generations is?

binary fission

oncogene

cancerous

hormones

chemicals used in long distance signaling

aneuploidy

condition in which offspring have an abnormal number of a particular chromosome

A carbon atom is most likely to form _____ bonds?

covalent

helicase

enzymes that untwist the double helix at the replication forks

cells are..

found only in prokaryotic eukaryotic organisms

epistasis

genetic phenomenon in which a gene at one locus alters the phenotypic expression of a gene at a second locus (FUR COLOR)

3 stages of translation

initiation, elongation, termination

Genetic variation in bacterial populations cannot result from?

meiosis

when a person get dehydrated while exercising on a hot day, their pituitary gland releases ADH, a hormone that signals the kidneys to retain more water. this is an example of...

negative feedback regulation

proto-oncogene

non cancerous

pathogens

parasites that cause disease

PCR

polymerase chain reaction

clone

product of asexual reproduction its offspring is genetically identical to the parent

apoptosis

programmed systematic cell death. Why is it important? to get rid of unhealthy cells, avoid crowding, get rid of material properly

reason for prokaryotes variation

rapid reproduction, mutation, and genetic recombination

three stages of cell signaling

reception, transduction, response

prokaryotic shapes

rod, spiral, sphere

Systematics

study of the diversity of life and the evolutionary relationships between organisms

biotechnology

tech that utilize biology to create products

Gram testing

technique that employs fluorescent dyes attached to probes to identify the location of specific mRNAs

horizontal gene transfer

the movement of genes among individuals from different species

euchromatin

the type light staining chromatin that is prevalent in cells that are active in the transcription of a variety of their genes

Which of the following is false regarding the complexity of biological systems?

understanding the chemical structure of DNA reveals how it directs the functioning of a living cell