First Semester Test 2007 – AP Biology

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Multiple Choice
Identify the choice that best completes the statement or answers the question.

Use the figure below to answer the following questions.

Which drawing depicts the electron configuration of neon (Ne)?

a.	Drawing A
b.	Drawing B
c.	Drawing C
d.	Drawing D
e.	Drawing E

Use the information extracted from the periodic table in the figure below to answer the following questions.

How many electrons does an atom of sulfur have in its valence shell?

a.	4
b.	6
c.	8
d.	16
e.	32

What is the valence of an atom with six electrons in its outer electron shell?

a.	1
b.	2
c.	3
d.	4
e.	5

What do atoms form when they share electron pairs?

a.	elements
b.	ions
c.	aggregates
d.	isotopes
e.	molecules

A van der Waals interaction is the weak attraction between

a.	the electrons of one molecule and the electrons of a nearby molecule.
b.	the nucleus of one molecule and the electrons of a nearby molecule.
c.	a polar molecule and a nearby nonpolar molecule.
d.	a polar molecule and a nearby molecule that is also polar.
e.	a nonpolar molecule and a nearby molecule that is also nonpolar.

The slight negative charge at one end of one water molecule is attracted to the slight positive charge of another water molecule. What is this attraction called?

a.	a covalent bond
b.	a hydrogen bond
c.	an ionic bond
d.	a hydrophilic bond
e.	a hydrophobic bond

Early 19th-century scientists believed that living organisms differed from nonliving things as a result of possessing a “life force” that could create organic molecules from inorganic matter. The term given to this belief is

a.	organic synthesis.
b.	vitalism.
c.	mechanism.
d.	organic evolution.
e.	inorganic synthesis.

Which of the following contains nitrogen in addition to carbon, oxygen, and hydrogen?

a.	an alcohol such as ethanol
b.	a monosaccharide such as glucose
c.	a steroid such as testosterone
d.	an amino acid such as glycine
e.	a hydrocarbon such as benzene

In which of the structures are the atoms bonded by ionic bonds?

a.	A
b.	B
c.	C
d.	C, D, and E only
e.	none of the structures

Use the figure below to answer the following questions.

Which is a carbonyl functional group?

a.	Group A
b.	Group B
c.	Group C
d.	Group D
e.	Group E

Use the molecules shown in the figure below to answer the following questions..

Which molecule contains an amino functional group, but is not an amino acid?

a.	Molecule A
b.	Molecule B
c.	Molecule C
d.	Molecule D
e.	Molecule E

Upon chemical analysis, a particular protein was found to contain 556 amino acids. How many peptide bonds are present in this protein?

a.	139
b.	554
c.	555
d.	556
e.	558

The figure below best illustrates the

a.	secondary structure of a polypeptide.
b.	tertiary structure of a polypeptide.
c.	quaternary structure of a protein.
d.	double helix structure of DNA.
e.	primary structure of a polysaccharide.

The R group or side chain of the amino acid serine is –CH2-OH. The R group or side chain of the amino acid alanine is –CH3. Where would you expect to find these amino acids in a globular protein in aqueous solution?

a.	Serine would be in the interior, and alanine would be on the exterior of the globular protein.
b.	Alanine would be in the interior, and serine would be on the exterior of the globular protein.
c.	Both serine and alanine would be in the interior of the globular protein.
d.	Both serine and alanine would be on the exterior of the globular protein.
e.	Both serine and alanine would be in the interior and on the exterior of the globular protein.

The following questions are based on the 15 molecules illustrated below. Each molecule may be used once, more than once, or not at all.

Which of the following molecules is (are) a carbohydrate?

a.	1 and 4
b.	6
c.	12
d.	5 and 14
e.	all of the above

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?

a.	ribosomes, nucleus, mitochondria
b.	chloroplasts, ribosomes, vacuoles
c.	nucleus, ribosomes, chloroplasts
d.	vacuoles, ribosomes, nucleus
e.	nucleus, mitochondria, ribosomes

Which of the following are prokaryotic cells?

a.	plants
b.	fungi
c.	bacteria
d.	animals
e.	B and C only

Which of the following comparisons between prokaryotic and eukaryotic cells is incorrect?

a.	The lack of organelles in prokaryotes means that they are structurally less complex than eukaryotes.
b.	The lack of internal membranes means that prokaryotes cannot compartmentalize function to the same extent as eukaryotes.
c.	All membrane function in prokaryotes is accomplished in the plasma membrane, while in eukaryotes, these functions are more distributed among the organelles.
d.	The specialization of function in organelles suggests that eukaryotes will contain a wider variety of phospholipids than prokaryotes.
e.	The lack of organelles in prokaryotes means that the basic cellular functions are different in prokaryotes than in eukaryotes.

Which of the following statements correctly describes some aspect of protein excretion in prokaryotic cells?

a.	Prokaryotes are unlikely to be able to excrete proteins because they lack an endomembrane system.
b.	The mechanism of protein excretion in prokaryotes is probably the same as that in eukaryotes.
c.	Proteins that are excreted by prokaryotes are synthesized on ribosomes that are bound to the cytoplasmic surface of the plasma membrane.
d.	In prokaryotes, the ribosomes that are used for the synthesis of secreted proteins are located outside of the cell.
e.	Prokaryotes contain large pores in their plasma membrane that permit the movement of proteins out of the cell.

All of the following structures and proteins are directly associated with movement in cells or by cells except

a.	cilia.
b.	dynein.
c.	actin.
d.	flagella.
e.	centrosomes.

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 terms of composition?

a.	microtubules
b.	microfilaments
c.	plant cell walls
d.	intermediate filaments
e.	nuclear lamina

The surface of an integral membrane protein would be best described as

a.	hydrophilic.
b.	hydrophobic.
c.	amphipathic.
d.	completely covered with phospholipids.
e.	exposed on only one surface of the membrane.

Which of the following is a reasonable explanation for why unsaturated fatty acids help keep any membrane more fluid at lower temperatures?

a.	The double bonds form a kink in the fatty acid tail, forcing adjacent lipids to be further apart.
b.	Unsaturated fatty acids have a higher cholesterol content.
c.	Unsaturated fatty acids permit more water in the interior of the membrane.
d.	The double bonds block interaction among the hydrophilic head groups of the lipids.
e.	The double bonds result in a shorter fatty acid tail.

Of the following functions, which is most important for the glycoproteins and glycolipids of animal cell membranes?

a.	facilitated diffusion of molecules down their concentration gradients
b.	active transport of molecules against their concentration gradients
c.	maintaining the integrity of a fluid mosaic membrane
d.	maintaining membrane fluidity at low temperatures
e.	a cell’s ability to distinguish one type of neighboring cell from another

What membrane-surface molecules are thought to be most important as cells recognize each other?

a.	phospholipids
b.	integral proteins
c.	peripheral proteins
d.	cholesterol
e.	glycoproteins

Which of the following is (are) true for anabolic pathways?

a.	They do not depend on enzymes.
b.	They are highly regulated sequences of chemical reactions.
c.	They consume energy to build up polymers from monomers.
d.	They release energy as they degrade polymers to monomers.
e.	both B and C

Which of the following statements about metabolism is incorrect?

a.	Metabolism is an emergent property of life at the level of organisms.
b.	Metabolism manages the utilization of materials and energy resources.
c.	The uptake of water associated with the hydrolysis of biological polymers is part of metabolism.
d.	Metabolism depends on a constant supply of energy.
e.	None of these statements about metabolism is incorrect.

Which of the following statements is not representative of the second law of thermodynamics?

a.	Conversion of energy from one form to another is always accompanied by some loss of free energy.
b.	Heat represents a form of energy that cannot be used by most organisms to do work.
c.	Without an input of energy, organisms would tend towards increasing entropy.
d.	Cells require a constant input of energy to maintain their high level of organization.
e.	Every energy transformation by a cell decreases the entropy of the universe.

Why is ATP an important molecule in metabolism?

a.	Its hydrolysis provides an input of free energy for exergonic reactions.
b.	It provides energy coupling between exergonic and endergonic reactions.
c.	Its terminal phosphate group contains a strong covalent bond that when hydrolyzed releases free energy.
d.	A and B only
e.	A, B and C

Many different things can alter enzyme activity. Which of the following underlie all types of enzyme regulation?

a.	changes in the activation energy of the reaction
b.	changes in the active site of the enzyme
c.	changes in the free energy of the reaction
d.	A and B only
e.	A, B, and C

The following questions are based on the reaction A + B C + D shown in the figure below.

Which of the following bests describes the reaction?

a.	negative G, spontaneous
b.	positive G, nonspontaneous
c.	positive G, exergonic
d.	negative G, endergonic
e.	G of zero, chemical equilibrium

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

a.	anabolic pathways
b.	catabolic pathways
c.	fermentation pathways
d.	thermodynamic pathways
e.	bioenergetic pathways

Which of the following statements about glycolysis false?

a.	Glycolysis has steps involving oxidation-reduction reactions.
b.	The enzymes of glycolysis are located in the cytosol of the cell.
c.	Glycolysis can operate in the complete absence of O2.
d.	The end products of glycolysis are CO2 and H2O.
e.	Glycolysis makes ATP exclusively through substrate-level phosphorylation.

Inside an active mitochondrion, most electrons follow which pathway?

a.	glycolysis NADH oxidative phosphorylation ATP oxygen
b.	citric acid cycle FADH2 electron transport chain ATP
c.	electron transport chain citric acid cycle ATP oxygen
d.	pyruvate citric acid cycle ATP NADH oxygen
e.	citric acid cycle NADH electron transport chain oxygen

Fermentation takes place in the

a.	cytosol.
b.	mitochondrial outer membrane.
c.	mitochondrial inner membrane.
d.	mitochondrial intermembrane space.
e.	mitochondrial matrix.

Muscle cells in oxygen deprivation convert pyruvate to ____, and in this step gain____.

a.	lactate; ATP
b.	alcohol; CO2
c.	alcohol; ATP
d.	ATP; NADH2
e.	lactate; NAD+

In alcohol fermentation, NAD+ is regenerated from NADH during the

a.	reduction of acetaldehyde to ethanol (ethyl alcohol).
b.	oxidation of pyruvate to acetyl CoA.
c.	reduction of pyruvate to form lactate.
d.	oxidation of NAD+ in the citric acid cycle.
e.	phosphorylation of ADP to form ATP.

What does the chemiosmotic process in chloroplasts involve?

a.	establishment of a proton gradient
b.	diffusion of electrons through the thylakoid membrane
c.	reduction of water to produce ATP energy
d.	movement of water by osmosis into the thylakoid space from the stroma
e.	formation of glucose, using carbon dioxide, NADPH, and ATP

Which statement is false?

a.	Thylakoid membranes contain the photosynthetic pigments.
b.	The O2 released during photosynthesis comes from water.
c.	RuBP is produced during cyclic electron flow in the light reactions of photosynthesis.
d.	The light reactions of photosynthesis provide the energy for the Calvin cycle.
e.	When chlorophyll is reduced, it gains electrons.

In C4 photosynthesis, carbon fixation takes place in the ____ cells, and then is transferred as malic or aspartic acid to ____ cells, where carbon dioxide is released for entry into the Calvin cycle.

a.	mesophyll; bundle-sheath
b.	stomatal; mesophyll
c.	bundle-sheath; epidermal
d.	epidermal; mesophyll
e.	stomatal; epidermal

What could happen to the target cells in an animal that lack receptors for local regulators?

a.	They could compensate by receiving nutrients via an a factor.
b.	They could develop normally in response to neurotransmitters instead.
c.	They could divide but never reach full size.
d.	They would not be able to multiply in response to growth factors from nearby cells.
e.	Hormones would not be able to interact with target cells.

G proteins and G-protein-linked receptors

a.	are found only in animal cells.
b.	are found only in bacterial cells.
c.	are thought to have evolved very early, because of their similar structure and function in a wide variety of modern organisms whose common ancestors diverged billions of years ago.
d.	probably evolved from an adaptation of the citric acid cycle.
e.	are not widespread in nature and were unimportant in the evolution of eukaryotes.

Membrane receptors that attach phosphates to specific amino acids in proteins are

a.	not found in humans.
b.	called receptor tyrosine-kinases.
c.	a class of GTP G-protein signal receptors.
d.	associated with several bacterial diseases in humans.
e.	important in yeast mating factors that contain amino acids.

The receptors for a group of signaling molecules known as growth factors are often

a.	ligand-gated ion channels.
b.	G-protein-linked receptors.
c.	cyclic AMP.
d.	receptor tyrosine kinases.
e.	neurotransmitters.

Sutherland discovered that epinephrine

a.	signals bypass the plasma membrane of cells.
b.	lowers blood glucose by binding to liver cells.
c.	interacts with insulin inside muscle cells.
d.	interacts directly with glycogen phosphorylase.
e.	elevates the cytosolic concentration of cyclic AMP.

The general name for an enzyme that transfers phosphate groups from ATP to a protein is

a.	phosphorylase.
b.	phosphatase.
c.	protein kinase.
d.	ATPase.
e.	protease.

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

a.	G-protein-linked receptor signaling
b.	ligand-gated ion channel signaling
c.	adenylyl cyclase activity
d.	phosphatase activity
e.	receptor tyrosine kinase activity

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

a.	10
b.	20
c.	30
d.	40
e.	80

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?

a.	anaphase
b.	prophase
c.	telophase
d.	metaphase
e.	interphase

Regarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants

a.	the spindles contain microfibrils in addition to microtubules, whereas animal spindles do not contain microfibrils.
b.	sister chromatids are identical, but they differ from one another in animals.
c.	a cell plate begins to form at telophase, whereas animals a cleavage furrow is initiated at that stage.
d.	chromosomes become attached to the spindle at prophase, whereas in animals chromosomes do not become attached until anaphase.
e.	spindle poles contain centrioles, whereas spindle poles in animals do not.

Which of the following is true concerning cancer cells?

a.	They do not exhibit density-dependent inhibition when growing in culture.
b.	When they stop dividing, they do so at random points in the cell cycle.
c.	They are not subject to cell cycle controls.
d.	B and C only
e.	A, B, and C

Which of the following is true of a species that has a chromosome number of 2n = 16?

a.	The species is diploid with 32 chromosomes.
b.	The species has 16 sets of chromosomes.
c.	There are 8 homologous pairs.
d.	During the S phase of the cell cycle there will be 32 separate chromosomes.
e.	A gamete from this species has 4 chromosomes.

Which of the following is the term for a human cell that contains 22 pairs of autosomes and two X chromosomes?

a.	an unfertilized egg cell
b.	a sperm cell
c.	a male somatic cell
d.	a female somatic cell
e.	both A and D

In animals, meiosis results in gametes, and fertilization results in

a.	spores.
b.	gametophytes.
c.	zygotes.
d.	sporophytes.
e.	clones.

All of the following are functions of meiosis in plants except

a.	production of spores.
b.	reduction of chromosome number by half.
c.	independent assortment of chromosomes.
d.	crossing over and recombination of homologous chromosomes.
e.	production of identical daughter cells.

Which of the following is true of the process of meiosis?

a.	Two diploid cells result.
b.	Four diploid cells result.
c.	Four haploid cells result.
d.	Four autosomes result.
e.	Four chiasmata result.

Which sample might represent an animal cell in G2 phase of the cell cycle?

a.	I
b.	II
c.	III
d.	both I and II
e.	both II and III

The following questions refer to the essential steps in meiosis described below.

1. formation of four new nuclei, each with half the chromosomes present in the parental nucleus

2. alignment of tetrads at the metaphase plate

3. separation of sister chromatids

4. separation of the homologues; no uncoupling of the centromere

5. synapsis; chromosomes moving to the middle of the cell in pairs

From the descriptions above, which of the following is the order that most logically illustrates a sequence of meiosis?

a.	1, 2, 3, 4, 5
b.	5, 4, 2, 1, 3
c.	5, 3, 2, 4, 1
d.	4, 5, 2, 1, 3
e.	5, 2, 4, 3, 1

Which of the following statements about Mendel’s breeding experiments is correct?

a.	None of the parental (P) plants were true-breeding.
b.	All of the F2 progeny showed a phenotype that was intermediate between the two parental (P) phenotypes.
c.	Half of the F1 progeny had the same phenotype as one of the parental (P) plants, and the other half had the same phenotype as the other parent.
d.	All of the F1 progeny resembled one of the parental (P) plants, but only some of the F2 progeny did.
e.	none of the above

A cross between homozygous purple-flowered and homozygous white-flowered pea plants results in offspring with purple flowers. This demonstrates

a.	the blending model of genetics.
b.	true-breeding.
c.	dominance.
d.	a dihybrid cross.
e.	the mistakes made by Mendel.

When crossing a homozygous recessive with a heterozygote, what is the chance of getting an offspring with the homozygous recessive phenotype?

a.	0%
b.	25%
c.	50%
d.	75%
e.	100%

P = purple, pp = white. The offspring of a cross between two heterozygous purple-flowering plants (Pp Pp) results in

a.	all purple-flowered plants.
b.	purple-flowered plants and white-flowered plants.
c.	two types of white-flowered plants: PP and Pp.
d.	all white-flowered plants.
e.	all pink-flowered plants.

A couple has three children, all of whom have brown eyes and blond hair. Both parents are homozygous for brown eyes (BB) but one is a blond (rr) and the other is a redhead (Rr). What is the probability that their next child will be a brown-eyed redhead?

a.	1/16
b.	1/8
c.	1/4
d.	1/2
e.	1

Which of the following is true regarding linkage maps? They

a.	always have a total of 100 map units.
b.	can be used to pinpoint the precise physical position of a gene on a chromosome.
c.	are a genetic map based on recombination frequencies.
d.	require preparation of karyotypes.
e.	reflect the frequency of crossing over between X and Y chromosomes.

The figure below represents the stained nucleus from a cheek epithelial cell of an individual whose genotype would probably be

a.	XX.
b.	XY.
c.	XYY.
d.	XXX.
e.	XXY.