Independent assortment of chromosomes occurs during _____.
A) meiosis I only
B) meiosis II only
C) mitosis and meiosis I
D) mitosis and meiosis II
Asexual reproduction in yeasts occurs by budding. Due to unequal cytokinesis, the
“bud” cell receives less cytoplasm than the parent cell. Which of the following should
be true of the smaller cell until it reaches the size of the larger cell?
A) It should produce fewer fermentation products per unit time.
B) It should be transcriptionally less active.
C) It should have reduced motility.
D) It should have a smaller nucleus.
A single base substitution mutation is least likely to be deleterious when the base
change results in _____.
A) a stop codon
B) a codon that specifies the same amino acid as the original codon
C) an amino acid substitution that alters the tertiary structure of the protein
D) an amino acid substitution at the active site of an enzyme
Which molecule shown above contains an amino functional group, but is NOT an
amino acid?
A) A
B) B
C) C
D) D
You have a freshly prepared 0.1 M glucose solution. Each liter of this solution contains
how many glucose molecules?
A) 6.02 x 1023
B) 3.01 x 1023
C) 6.02 x 1024
D) 6.02 x 1022
Use the following information to answer the questions below.
Exposing inner mitochondrial membranes to ultrasonic vibrations will disrupt the
membranes. However, the fragments will reseal “inside out.” The little vesicles that
result can still transfer electrons from NADH to oxygen and synthesize ATP.
After the disruption, when electron transfer and ATP synthesis still occur, what must be
present?
A) all of the electron transport proteins and ATP synthase
B) all of the electron transport system and the ability to add CoA to acetyl groups
C) the ATP synthase system
D) the electron transport system
Transpiration in plants requires _____.
I) adhesion of water molecules to cellulose
II) cohesion between water molecules
III) evaporation of water molecules
IV) active transport through xylem cells
V) transport through tracheids
A) I, III, IV, and V
B) I, II, IV, and V
C) I, II, III, and V
D) I, II, III, and IV
One hypothesis that has been proposed regarding the origin of life suggests that life
evolved from an “RNA world” to today’s “DNA world.” Considering the properties of
RNA and DNA molecules, which questions would direct an investigation of the most
insightful test(s) of this hypothesis?
A) Is it likely that RNA molecules functioned as ribozymes to synthesize DNA from
amino acids, and that this role was reversed when DNA became the information source?
B) Is it likely that simple, yet stable RNA molecules served as a primitive precursor to a
less stable DNA molecule that was more capable of storing more information?
C) Could RNA have provided a template for DNA assembly, thereby enabling a more
stable molecule that is replicated more accurately?
D) Since ribozymes could freely enter and leave the vesicles, could these molecules
have brought external DNA into the cell as a less stable, but more reliable storage
molecule of double-stranded DNA?
After looking at the experiment in the figure above, what can be said about productivity
in marine ecosystems?
A) Nothing can be said based on this information.
B) Marine organisms break down iron for energy and thus for productivity.
C) Iron can be a limiting nutrient in productivity.
D) Productivity increases when chlorophyll a is added.
Which of the following locations are major reservoirs for carbon for the carbon cycle?
I) atmosphere
II) sediments and sedimentary rocks
III) fossilized plant and animal remains (coal, oil, and natural gas)
IV) plant and animal biomass
A) only I and III
B) only II and IV
C) only II, III, and IV
D) I, II, III, and IV
Use the survivorship curves in the figure below to answer the following questions.
Refer to the figure above. Which curve best describes survivorship in elephants?
A) A
B) B
C) C
D) E
Which of the following statements is true about a phylogeny, as represented by a
phylogenetic tree?
I) Descendant groups (branches) from the same node do not necessarily share any
derived characters.
II) A monophyletic group can be properly based on convergent features.
III) The ancestral group often has all the synapomorphies of the descendant species.
A) only I
B) only II
C) only III
D) None. Not I, II, or III.
In respiration, beta oxidation involves the _____.
A) oxidation of glucose
B) oxidation of pyruvate
C) regulation of glycolysis
D) breakdown of fatty acids
Scientific theories _____.
A) are nearly the same things as hypotheses
B) are supported by, and make sense of, many observations
C) cannot be tested because the described events occurred only once
D) are predictions of future events
During aerobic respiration, electrons travel downhill in which sequence?
A) glucose → NADH → electron transport chain → oxygen
B) glucose → pyruvate → ATP → oxygen
C) glucose → ATP → electron transport chain → NADH
D) food → glycolysis → citric acid cycle → NADH → ATP
The following table depicts characteristics of five prokaryotic species (A-E). Use the
information in the table to answer the question(s) below
Which two species might be expected to cooperate metabolically, perhaps forming a
biofilm wherein one species surrounds cells of the other species?
A) species A and B
B) species A and C
C) species B and E
D) species C and D
When a person drinks alcohol, the rate of urination increases. This suggests that
antidiuretic hormone (ADH) may be affected by alcohol consumption in some way.
Which of the following best accounts for the increase in urination?
A) Alcohol stimulates the release of ADH.
B) Alcohol inhibits the release of ADH.
C) Alcohol inhibits the binding of ADH to receptors in the nephron.
D) Alcohol could inhibit ADH release or the binding of ADH to receptors in the
nephron.
The cow Bos primigenius (which is bred for meat and milk) has a smaller brain and
larger eyes than closely related wild species of ungulates. These traits most likely arose
by _____.
A) natural selection, because these traits evolved in the population over time
B) natural selection, because these traits were not consciously selected by humans
C) artificial selection, because changes in these traits co-occurred with human selection
for high milk output and high muscle content
D) artificial selection, because these animals differ from their close relatives and
common ancestor
If you applied a fungicide to a cornfield, what would you expect to happen to the rate of
decomposition and net ecosystem production (NEP)?
A) Both decomposition rate and NEP would decrease.
B) Both decomposition rate and NEP would increase.
C) Decomposition rate would increase and NEP would decrease.
D) Decomposition rate would decrease and NEP would increase.
The cerebrospinal fluid is _____.
A) a filtrate of the blood
B) a secretion of glial cells
C) cytosol secreted from ependymal cells
D) secreted by the hypothalamus
Most of the chemosensory neurons arising in the nasal cavity have axonal projections
that terminate in the _____.
A) gustatory complex
B) olfactory bulb
C) occipital lobe
D) posterior pituitary gland
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?
A) Molybdenum atoms can have between 50 and 58 neutrons.
B) Molybdenum atoms can have between 50 and 58 protons.
C) Molybdenum atoms can have between 50 and 58 electrons.
D) Isotopes of molybdenum have different numbers of electrons.
In humans, ABO blood types refer to glycoproteins in the membranes of red blood
cells. There are three alleles for this autosomal gene: IA, IB, and i. The IA allele codes
for the A glycoprotein, The IB allele codes for the B glycoprotein, and the i allele
doesn’t code for any membrane glycoprotein. IA and IB are codominant, and i is
recessive to both IA and IB. People with type A blood have the genotypes IAIA or IAi,
people with type B blood are IBIB or IBi, people with type AB blood are IAIB, and
people with type O blood are ii. If a woman with type AB blood marries a man with
type O blood, which of the following blood types could their children possibly have?
A) A and B
B) AB and O
C) A, B, and O
D) A, B, AB, and O
What would happen to the seasons if the Earth were tilted 35 degrees off its orbital
plane instead of the usual 23.5 degrees?
A) The seasons would disappear.
B) Winters and summers would be more severe.
C) Winters and summers would be less severe.
D) The seasons would be shorter.
In hybrid zones where reinforcement is occurring, we should see a decline in _____.
A) gene flow between distinct gene pools
B) speciation
C) the genetic distinctness of two gene pools
D) mutation rates
How could you genetically modify an animal so that it would distinguish more shades
of green?
A) Induce genes to produce a greater number of cone cells in the fovea.
B) Introduce genes for different opsins that respond in the green region of the spectrum.
C) Introduce genes to produce green fluid in the eyeball, because green fluids will not
absorb green light.
D) Induce increased production of cGMP to increase opening of cGMP-gated sodium
channels.
The following questions refer to the evolutionary tree in the figure below.
The horizontal axis of the cladogram depicted below is a timeline that extends from
100,000 years ago to the present; the vertical axis represents nothing in particular. The
labeled branch points on the tree (V-Z) represent various common ancestors. Let’s say
that only since 50,000 years ago has there been enough variation between the lineages
depicted here to separate them into distinct species, and only the tips of the lineages on
this tree represent distinct species.
Which pair of scientists below would probably have agreed with the process that is
depicted by this tree?
A) Cuvier and Lamarck
B) Lamarck and Wallace
C) Aristotle and Lyell
D) Wallace and Linnaeus
If a biochemist discovers a new molecule, which of the following pieces of data would
allow her to draw the conclusion that the molecule is a steroid hormone?
I) The molecule is lipid soluble.
II) The molecule is derived from a series of steps beginning with cholesterol.
III) The molecule acts at a target tissue some distance from where it is produced.
IV) The molecule uses a carrier protein when in an aqueous solution such as blood.
A) only I and III
B) only II and IV
C) only I, III, and IV
D) I, II, III, and IV
Which of the following is the meaning of the chromosome theory of inheritance as
expressed in the early twentieth century?
A) Individuals inherit particular chromosomes attached to genes.
B) Mendelian genes are at specific loci on the chromosome and, in turn, segregate
during meiosis.
C) No more than a single pair of chromosomes can be found in a healthy normal cell.
D) Natural selection acts on certain chromosome arrays rather than on genes.
Use the following information to answer the question(s) below.
“Marine cone snails from the genus Conus are estimated to consist of up to 700 species.
These predatory molluscs have devised an efficient venom apparatus that allows them
to successfully capture polychaete worms, other molluscs, or in some cases fish as their
primary food sources. ” conotoxins from Australian species of Conus ” have the
capacity to inhibit specifically the nicotinic acetylcholine receptors in higher animals.”
(B. G. Livett, K. R. Gayler, and Z. Khalil. 2004. Drugs from the sea: Conopeptides as
potential therapeutics. Current Medicinal Chemistry 11:1715-23.)
Refer to the paragraph above on the venom of marine core snails. This particular
conotoxin inhibits acetylcholine receptors that are located _____.
A) along the motor neuron axon
B) on motor neuron dendrites
C) on the presynaptic membrane of the neuromuscular junction
D) on the postsynaptic membrane, on the muscle cell