Biology Final Notes

Scientists use the term ____________ to refer to the genetic makeup for that organism.

genotype

What carbohydrate energy storage molecule is found in animal liver and muscle cells?

glycogen

A cell in the G2 phase

has twice the amount of DNA present in a telophase nucleus.

The covalent bond between a hydrogen atom and the oxygen atom in water is formed when:

hydrogen and oxygen share an electron pair.

Which of the following is responsible for the alpha-helical structure of proteins?

hydrogen bonds

If the concentration of solutes in a cell is less than the concentration of solutes in the surrounding fluid, then the extracellular fluid is said to be

hypertonic.

What organic molecules is the primary structural component of cell membranes?

phospholipids

In the accompanying figure, fertilization occurs within which of the labeled structures?

1

Cystic fibrosis is an autosomal recessive disease. A couple formed by healthy heterozygote woman and a man with cystic fibrosis have had three girls with cystic fibrosis, and are hoping to have a fourth child. What are the chances that the fourth child will be again a girl with cystic fibrosis?

1/4

An individual who inherits the specific chromosome ____ deletion from his/her ____ will most likely have Prader-Willi syndrome rather than Angelman syndrome.

15; father

Arrange the following stages of oogenesis in sequential order. (1) Secondary oocyte (2) Oogonium (3) Ovum (4) Primary oocyte

2 → 4 → 1 → 3

After ovulation, the ovum remains fertile for about:

24 hours

What is the haploid number for this karyotype?

27

Refer to the accompanying figure. Which of the labeled structures refers to the prostate gland?

3

The color of pea plants from a cross between parent plants heterozygous for color, in which yellow is recessive, would be:

3 green : 1 yellow

The height of pea plants from a cross between parent plants heterozygous for height, in which tall is dominant, would be

3 tall: 1 short.

A chlorine atom has 17 protons and 18 neutrons. What is its atomic mass?

35 amu

A heterozygous fruit fly with normal wings and red eyes (VvRr) is crossed with flies with vestigial wings and red eyes (vvRr). If there are 1000 F1 progeny, the expected phenotypes would be:

375 normal red, 125 normal black, 375 vestigial red, and 125 vestigial black

The normal human karyotype contains ____ total chromosomes, consisting of ____ autosomes and ____ sex chromosomes.

46; 22; 2

Arrange the stages of sperm development in chronological order. (1) Sperm (2) Spermatid (3) Primary spermatocyte (4) Secondary spermatocyte (5) Spermatogonium

5 → 3 → 4 → 2 → 1

Due to a rapid change in the environment, a population of ants was reduced from one million to one thousand. What type of genetic drift will occur in the gene pool of this population when it expands again?

A genetic bottleneck

Suppose that acetylcholine binds its receptor on the surface of a muscle cell. What happens next?

A sodium gate opens.

What is required for facilitated diffusion to take place?

A transmembrane protein

What does an ABC transporter use to move larger ions and molecules across the cell membrane?

ATP

Translation is initiated at the ____.

AUG codon

Based on the accompanying figure, which two present day continents should have the most closely related plant and animal species?

Africa and South America

Whose findings of evolution by natural selection were presented with those of Darwin?

Alfred Wallace

Colorblindness is an X-linked recessive trait. What are the predicted phenotypes of the offspring between a colorblind woman and a man with normal vision?

All male offspring is color blind and all females have normal vision

Since sodium-potassium pumps transport sodium ions out of a cell and potassium ions into a cell, what type of carrier proteins are they?

Antiporters

What are the possible phenotypes of the children if the mother's genotype is ii for blood type and the father is IBi?

B, O

What are the possible genotype(s) for locus B that would result from a cross between a heterozygous individual and a homozygous individual that shows a dominant phenotype?

BB and Bb

Which of the following represents the possible genotype(s) resulting from a cross between a heterozygous individual (Bb) and one that is homozygous (bb)?

Bb and bb

What happens during the cotransport of glucose and sodium ions?

C. Both D and E d. Glucose molecules are transported against their concentration gradient. e. Sodium ions are transported down their concentration gradient.

In the lac operon, cAMP binds to:

CAP

Which is an example of a second messenger?

Cyclic AMP

What type of selection is represented by the accompanying figure?

Disruptive selection

Which of the following describes how facilitated diffusion is powered?

Energy is required to do the work of establishing and maintaining a concentration gradient.

When atoms react to form an ionic bond, electrons are shared between those atoms.

False

With deductive reasoning, you draw conclusions from specific observations.

False

Sexual reproduction involves which of the following processes?

Fertilization

The hydrolysis of GTP to GDP deactivates the ____.

G protein

What best describes all alleles for all of the loci present in a population?

Gene pool

What is the land mass labeled as 2 in the accompanying figure?

Gondwana

What evolutionary advantage is provided by sexual reproduction?

Increased genetic diversity

Why is the Hardy-Weinberg principle useful to biologists?

It identifies those factors that can change allele or genotype frequencies.

Which best describes the effect of positive assortative mating in a population?

It increases homozygosity

Which is a characteristic of a good hypothesis?

It is falsifiable.

When does an atom becomes a cation?

It loses one or more electron.

Who is responsible for the first concept regarding the passing on traits or characteristics that were acquired during the lifetime of an organism to its offspring?

Jean Baptiste de Lamarck

In the female, ____ stimulates ovulation.

LH

The genotype for a frog that is homozygous dominant for long legs (locus L) and homozygous recessive for green color (locus G) would be:

LLgg

Which of the following sequences is correct?

Males: gonadotropin-releasing hormone: stimulate LH and FSH secretion

Which hormone causes contraction of the uterus?

Oxytocin

Which of the following statements characterizes PCR?

PCR replicates specific DNA sequences

Transcriptional activation of the lac operon requires both high lactose and low glucose conditions because:

RNA polymerase requires CAP in order to bind to the lacoperon promoter, even in the absence of the repressor.

Which is an example of nonrandom mating?

Selecting a mate by their phenotype

Which hormone stimulates masculine physical characteristics?

Testosterone

When is a cell in metaphase?

The chromosomes are aligned at the midplane of the cell

Under which of the following situations would receptor downregulation most likely occur?

The concentration of a hormone is too high

How is the four-letter language of nucleic acids converted into the 20-word language of amino acids?

The four nucleic acid bases combine in three-letter sequences that define different amino acids.

What does p2 represent within the Hardy-Weinberg equation?

The homozygous dominant genotype at a given locus

You have identified a new mammal species. You are surprised to find that it has a pelvis, but there is no evidence the species has legs. What can you conclude about this animal's structure?

The pelvis is a vestigial structure

Two species have homologous structures. What can we infer?

The species are related by a common ancestry

For the relative proportions of alleles and genotypes in successive generations to stay the same, which condition must be met for the population?

There can be no natural selection

Which is a property of unsaturated fats?

They are generally liquid at room temperature.

Which statement about van der Waal interactions is false?

They are very strong.

Which statement about centrioles is false?

They have a 9 + 2 arrangement of microtubules

Four of the following ideas are consistent with Darwinian evolution.Which one is the exception?

Traits acquired during an individual's life are passed on to its offspring.

An atom X contains 14 protons, 13 electrons, and 12 neutrons, and atom Y contains 14 protons, 14 electrons, and 12 neutrons. What can you conclude?

X and Y are atoms of the same element.

What is a distinct characteristic of asexual reproduction?

a cell splitting into identical halves

Aneuploidies describe:

a condition in which an extra chromosome is present or one is absent

Evolution is genetic change in ____ that occurs over time.

a population

Cloning mammals has proven to be:

a process with a low success rate and a high incidence of genetic defects

The cis face of the Golgi complex is most directly involved in which process?

accepting vesicles from the ER

The 3′ end of eukaryotic pre-mRNAs is changed by:

adding 100−250 adenine nucleotides

The concept of nuclear equivalence states that:

all of the somatic cells in an adult organism have the same genes.

Mendel's principle of segregation states that

alleles separate from each other before forming gametes

Introns in pre-mRNA:

are spliced out of the message.

In the construction of a DNA library, bacterial colonies that grow on agar plates containing antibiotic can be described as:

arising from one individual bacterium that contained a recombinant plasmid

What process has been used to produce many of today's vegetables, such as broccoli, kohlrabi, and cauliflower, which are all derived from wild cabbage?

artificial selection

What represents the most basic level of chemical organization?

atom

Which example best illustrates homoplasy?

bird wings and insect wings

Which cellular structure is correctly matched to the role it plays within the cell?

centrosome−cell division

DNA sequencing data suggest that evolutionary changes are related to an accumulation of:

changes in DNA nucleotide sequences

Eukaryotic chromosomes are composed of

chromatin

A bacterial chromosome consists of a

circular DNA molecule many times larger than the cell

Many genes encode proteins that are always needed by a cell, and therefore are always expressed. Such genes are known as:

constitutive

The type of bond illustrated in the accompanying diagram is a(n):

covalent bond

The process of ____ describes cell specialization structure and gene activity.

differentiation

A pear plant with the genotype Aa can produce gametes containing

either A or a

A frog with the genotype AABb can produce gametes containing:

either Ab or AB

The sodium-potassium pump is a carrier protein that maintains a(n) ____ gradient across the plasma membrane.

electrochemical

The rate of eukaryotic transcription after initiation is increased by:

enhancers

If the allele or genotype frequencies deviate from the values predicted by the Hardy-Weinberg principle, the population is:

evolving

In polymerase chain reaction technology, the two strands of DNA are separated by:

exposure to heat

Colorblindness is an X-linked recessive trait. What are the predicted genotypes of the offspring between a man and a woman who are both colorblind? a. XcXc, XCXc, XCY b. XCXc, XCY c. XCXc, XcY d. XcXc, XCY e. XCXC, XCXc, XCY, XcY f. XcXc, XcY

f

A cDNA library is complementary to DNA and thus does not contain introns

false

Adult stem cells are found only in adults.

false

Adult stem cells in the brain are totipotent and differentiate into neurons and glial cells.

false

Genome-wide association scans compare the proteins of individuals with a disease to individuals without the disease.

false

If a human gene containing introns is inserted into a prokaryote cell, a functional human protein will be produced.

false

In an operon, the switch that controls mRNA synthesis is the promotor, which is a sequence of bases upstream from the first structural gene.

false

In reciprocal translocation, two homologous chromosomes exchange segments

false

Males with Klinefelter syndrome lack a Barr Body.

false

Mendel's principle of independent assortment describes the separation of paired factors during the formation of gametes.

false

Mitochondria play an important role in cell necrosis.

false

Mutations in the TATA box increase the rate of transcription.

false

The baby is delivered during the third stage of labor.

false

The chain termination method of DNA sequencing is based on a replicating DNA strand incorporating a(n) deoxynucleotide that stops the chain elongation.

false

Variations that are acquired during the life of an individual that are favorable to the survival of an organism tend to be present in greater frequency in the next generation of those organisms.

false

When an enzyme linked receptor is activated, a conformational change activates the extracellular kinases.

false

The ____ develops into a corpus luteum.

follicle

In the accompanying figure, the purpose of growing the donor cells in nutrient-limited media is to:

force the donor cell nucleus into the G0 cell stage

The discovery of fossils of whale intermediates suggest that whales evolved from:

four-legged, land dwelling mammals

Both male and female gonads function to produce _____, _____, and _______.

gametes; hormones; secondary sexual characteristics

The migration of breeding individuals between populations causes a corresponding movement of alleles, which is referred to as:

gene flow

Scientific evidence in the field of developmental biology overwhelmingly demonstrates that development in different animals is controlled by the same kinds of:

genes

Bacteria can respond quickly to their surroundings, such as in the presence of an abundant food source. This is because

genes for functionally related enzymes are regulated together in operons.

A genomic library is a collection of:

genomic DNA fragments that are spliced into plasmids

After fertilization, which hormone is secreted by the developing embryo to maintain the function of the corpus luteum?

hCG

Refer to the accompanying figure. Based on the phenotypes of the third generation, the genotype of the father in the second generation must be:

heterozygous for albinism

The genotypes of the normal females in the second generation in the accompanying figure are:

heterozygous for albinism

In the accompanying figure, the purpose of electrical shock at the stage of the process labeled as A is to:

initiate fusion of the two cells

Frameshift mutations result from the

insertion or deletion of one or two base pairs

DNA ligase links two ____ DNA fragments by ____ bonds.

linear; covalent

Mendel found that in a species of frog native to Tennessee long legs and green color are dominant. The phenotype for a frog with the genotype LLgg would be:

long legs and brown color.

Nearly half of the pregnancies that end in miscarriage have:

major chromosomal abnormalities

Maternal effect genes of Drosophila are genes active in ____ cells, whose products establish ____ in developing embryos.

maternal; polarity

Malignant tumors are characterized by:

metastasis

Evolution that involves changes in allele frequencies over just a few successive generations is referred to as:

microevolution

You isolate a cellular structure and determine that it is composed of α-tubulin and β-tubulin. Based on this evidence, you correctly identify this structure as a(n):

microtubule

Which of the following organelles plays an important role in apoptosis, or programmed cell death?

mitochondria

The M phase of the cell cycle involves two main processes:

mitosis and cytokinesis.

Maternal effect genes form ____ gradients in the developing egg.

morphogen

Cells become progressively organized into recognizable structures through a process known as:

morphogenesis

Following peptide bond formation between the amino acid in the A site on the ribosome and the growing polypeptide chain, the tRNA in the A site:

moves to the P site of the ribosome

Proto-oncogenes can be converted to oncogenes by:

mutation

Variation is introduced into a population through _________________, which is an unpredictable change in deoxyribonucleic acid.

mutation

Which process provides the genetic variability that natural selection acts on during evolution?

mutation

The sperm in the figure below were most likely produced by:

nondisjunction

Where would you most likely find fossilized remains of humans and their immediate ancestors?

only in relatively young rock

In an inducible operon, the ____ is the molecular switch that controls gene expression, while the ____ is the DNA region where RNA polymerase binds to begin transcription.

operator; promoter

The genetic code demonstrates the universality of living things because it is common to virtually all:

organisms

Translocation occurs when:

part of a chromosome breaks off and attaches to a nonhomologous chromosome

Transformation is a process whereby:

plasmids are transferred into bacterial cells

A ____ consists of all of the individuals of the same species that inhabit a particular place at the same time.

population

What is an example of a limit on population growth, and proposed by Darwin to be a mechanism of evolution by natural selection?

predation

Which sequence represents the pattern of energy flow within an ecosystem?

producers → consumers → decomposers

The function of the epididymis is to:

provide a place for maturation and storage of sperm.

Translational controls regulate the:

rate at which an mRNA molecule is translated

Retroviruses, such as RNA tumor viruses, use __________ to make DNA from their RNA genomes.

reverse transcriptase

In a chromosomal inversion, a segment of a chromosome is:

reversed

The function of the bulbourethral gland is to

secrete mucus that lubricates the penis.

Comparing the human and mouse genomes has revealed that the mouse and human:

share most genes

Reverse transcriptase catalyzes the production of _____ from ____.

single-stranded cDNA; single-stranded mRNA

Homeotic genes of Drosophila:

specify the developmental plan(s) for each segment

Semen consists of:

sperm plus secretions of accessory glands.

In ____ selection, individuals with a phenotype near the mean are favored over those at the phenotypic extremes

stabilizing

Extensive data from hospitals have shown that infants born with intermediate weightsare the ones most likely to survive. This is a classic example of which type of selection?

stabilizing selection

Which functional group forms bridges to help stabilize a protein's quaternary structure?

sulfhydryl

In early Drosophila development, which of the following forms first?

syncytial blastoderm

The molecule that connects a growing polypeptide chain and mRNA is called:

tRNA

Darwin might have made greater advances in his theory of evolution by natural selection if he had:

taken into consideration the work of Gregor Mendel

Refer to the accompanying figure. The portion of the molecule labeled as 5 is:

the attached amino acid

All calico cats are female because

the calico phenotype is caused by random X chromosome inactivation

Repressible genes are usually actively transcribed when:

the end product of the enzymes encoded by these genes is low

The mutant fly in the accompanying figure illustrates

the existence of homeotic genes in Drosophila

Karyotyping is useful for determining:

the number of chromosomes in an individual

Down syndrome is characterized by:

the presence of 47 chromosomes per somatic cell

The amplification of recombinant plasmids occurs by:

the process of growth and division of the host cell

In elephants, the allele for big ears is dominant and the allele for small ears is recessive. If one elephant with big ears mates with an elephant with small ears and they have a baby elephant with small ears, that means:

there is a 1/2 chance that a second baby elephant will have big ears.

Nitrogen has five electrons in its valence shell. How many electrons does it need to gain to complete its valence shell?

three

Which description illustrates the tertiary structure of a protein molecule?

three-dimensional shape of an individual polypeptide chain

The role of ATP in the sodium-potassium pump is

to transfer Na+ to the outside of a cell.

Regulation of development takes place mostly at the level of:

transcription

An organism in which foreign genes have been incorporated is called a:

transgenic organism

A grouping of three nucleotides codes for one amino acid.

true

An atom having a filled valence shell is stable and unreactive.

true

In fragile X syndrome, the fragile X gene contains a nucleotide triplet that repeats 200 to 1000 times.

true

Polyploidy may arise from the failure of chromosomes to separate during cell division or by the fertilization of an egg by more than one sperm.

true

The poly-A tail is thought to facilitate the export of mRNA from the nucleus.

true

To produce a genomic library DNA, DNA fragments are incorporated into plasmids that are introduced into bacteria.

true

Genes that normally block cell division are called:

tumor suppressor genes

The gene that codes for the repressor protein of the E. coli lac operon is constitutive; therefore, the lac operon is typically:

turned off

If an animal population is diploid, then each individual possesses:

two alleles for each locus.

One secondary spermatocyte ultimately produces

two mature sperm

​In the accompanying figure, which combination of letters accurately represents two sister chromatids?

A and C

What is typically the result of receptor upregulation?

A hormone's signal is amplified.

____ are alternative forms of a gene that govern the same feature, such as eye color, and occupy corresponding positions on homologous chromosomes.

Alleles

What differentiates an organic compound from an inorganic compound?

An organic compound contains carbon

Which organizational unit includes the fewest species of organisms?

Population

​Which phase of cell division is depicted in the accompanying figure?

Prophase I of meiosis

In living organisms, chemical reactions responsible for growth, repair, and nutrition are collectively referred to as:

Metabolism

What is the passive movement of water along a concentration gradient?

Osmosis

____ are loosely associated with the phospholipid bilayer, whereas ____ are tightly bound to it.

Peripheral proteins; integral proteins

What is the process in which one activated receptor can give rise to thousands of final products?

Signal amplification

What type of molecule can rapidly cross a plasma membrane?

Small, hydrophobic molecules

What is not a hallmark of prophase?

Spindle fibers pull chromosomes to opposite sides of the cell.

Which is a benefit of sexual reproduction over asexual reproduction?

The interaction of the genes from both parents brings about genetic variation.

A basal body anchors what part of a cell?

flagellum

Which statement represents a good hypothesis?

The swimming speed of Artemia increases at higher temperatures.

Which process is a function of peroxisomes?

detoxification

What type of protein accelerates the thousands of different chemical reactions thattake place in an organism?

enzyme

A test cross is performed to determine phenotype.

false

An example of a(n) anion is K+.

false

Dominant traits remove recessive traits when both are present in the same individual.

false

For each animal cell that begins oogenesis, the number of ova produced is four.

false

Genotype can always be inferred from phenotype.

false

If solution of A is hypotonic to B, then the direction of net movement of water is B to A .

false

How many carbon sugars are there in a pentose sugar?

five

The cell cycle of a typical somatic cell consists of the ____ and M phases.

interphase

When the net movement of water in and out a cell is zero, that solution is said to be

isotonic.

Which statement concerning a scientific theory is FALSE?

it is unchangeable

If an allele is dominant, then

its phenotype masks the expression of the recessive allele in a hybrid.

Intermediate filaments are most closely associated with which of the following?

keratins

Typically, the gate of an ion channel remains closed until a(n) ____ binds to the receptor.

ligand

Plants lack organ systems for disposing of toxic metabolic waste products. Their cells' vacuoles are like what animal cell organelle?

lysosomes

Which is an example of a disaccharide?

maltose

The ____ is responsible for the separation of the chromosomes during the ____ of mitosis.

mitotic spindle; anaphase

Isotopes differ from each other with respect to the number of:

neutrons only

The largest and most complex assembly of proteins in most eukaryotic cells are the:

nuclear pores

Homologous chromosomes undergo synapsis during

prophase I.

The outer part of a G protein-linked receptor binds to a(n) ____, and its inner part binds to a(n) ____.

signaling molecule; G protein

A hypothesis can best be described as a(n):

tentative explanation

Mating an individual expressing a dominant phenotype, but whose genotype is unknown, with an individual expressing the corresponding recessive phenotype is an example of a(n)

test cross

The probability that two genes will be separated by crossing-over is related to

the distance between the two genes on the chromosome.

The term "fluid mosaic model" refers to

the movement of lipids and integral proteins within the lipid bilayer.

Cells that secrete large amounts of glycoprotein have many Golgi stacks.

true

Dosage compensation is defined as the genetic phenomenon that allows females, who carry two copies of an X-linked gene, to have a phenotype that is equivalent to that of males, who only have one copy of the X-linked gene.

true

Homologous pairs of chromosomes separate during meiosis I.

true

In animal cells, the main microtubule organizing center (or centrosome) is important in cell division.

true

Ion channels are found in the plasma membranes of neurons and muscle cells.

true

The genotype for a pea plant that is homozygous recessive for both height (locus T) and pea color (locus Y) would be:

ttyy