How would you classify the genetic basis for most behavioral traits in the animal
kingdom?
A) One gene typically codes for one behavior.
B) One gene typically codes for many behaviors.
C) Many genes typically code for one behavior.
D) Behaviors are learned, not coded by genes.
Which of the following is a primary difference between ectomycorrhizae and
endomycorrhizae?
A) Endomycorrhizae have thicker, shorter hyphae than ectomycorrhizae.
B) Ectomycorrhizae do not penetrate root cells, whereas endomycorrhizae grow into
invaginations of the root cell membranes.
C) Endomycorrhizae are more common than ectomycorrhizae.
D) There are no significant differences between ectomycorrhizae and endomycorrhizae.
Which of the following would you expect of a eukaryote lacking telomerase?
A) a high probability of somatic cells becoming cancerous
B) an inability to produce Okazaki fragments
C) an inability to repair thymine dimers
D) a reduction in chromosome length in gametes
If an organism has a relatively large number of Hox genes in its genome, it most likely
_____.
A) has Hox genes expressed in all cells of its body
B) has multiple paired appendages along the length of its body
C) has a relatively complex anatomy
D) belongs to one of the first groups to evolve on Earth
A mutant bacterial cell has a defective aminoacyl-tRNA synthetase that attaches a
lysine to tRNAs with the anticodon AAA instead of the normal phenylalanine. The
consequence of this for the cell will be that _____.
A) none of the proteins in the cell will contain phenylalanine
B) proteins in the cell will include lysine instead of phenylalanine at amino acid
positions specified by the codon UUU
C) the cell will compensate for the defect by attaching phenylalanine to tRNAs with
lysine-specifying anticodons
D) the ribosome will skip a codon every time a UUU is encountered
A ribozyme is _____.
A) a catalyst that uses RNA as a substrate
B) an RNA with catalytic activity
C) an enzyme that catalyzes the association between the large and small ribosomal
subunits
D) an enzyme that synthesizes RNA as part of the transcription process
What major advantage is conveyed by having a system of adaptive immunity?
A) It enables a rapid defense against an antigen that has been previously encountered.
B) It enables an animal to counter most pathogens almost instantly the first time they
are encountered.
C) It results in effector cells with specificity for a large number of antigens.
D) It allows for the destruction of antibodies.
A recent study compared the Homo sapiens genome with that of Neanderthals. The
results of the study indicated that there was a mixing of the two genomes at some
period in evolutionary history. Additional data consistent with this hypothesis could be
the discovery of _____.
A) some Neanderthal sequences not found in living humans
B) a few modern H. sapiens with some Neanderthal sequences
C) duplications of several Neanderthal genes on a Neanderthal chromosome
D) some Neanderthal chromosomes that are shorter than their counterparts in living
humans
Which of the following is a correct statement about the MacArthur/Wilson Island
Biogeography Model?
A) As the number of species on an island increases, the emigration rate decreases.
B) Competitive exclusion is less likely on an island that has large numbers of species.
C) Small islands receive few new immigrant species.
D) Islands closer to the mainland have higher extinction rates.
Inflammatory responses typically include _____.
A) increased activity of phagocytes in an inflamed area
B) reduced permeability of blood vessels to conserve plasma
C) release of substances to decrease the blood supply to an inflamed area
D) inhibiting the release of white blood cells from bone marrow
Some birds follow moving swarms of army ants in the tropics. As the ants march along
the forest floor hunting insects and small vertebrates, birds follow and pick off any
insects or small vertebrates that fly or jump out of the way of the ants. This situation is
an example of what kind of species interaction between the birds and the ants?
A) consumption
B) commensalism
C) parasitism
D) mutualism
If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more
antibiotic-resistance genes, what would happen in environments that lack antibiotics?
A) These genes would be maintained in case the antibiotics appear.
B) These bacteria would be outcompeted and replaced by bacteria that have lost these
genes.
C) These bacteria would try to make the cost worthwhile by locating and migrating to
microenvironments where traces of antibiotics are present.
D) The number of genes conveying antibiotic resistance would increase in these
bacteria.
Circannual rhythms in birds are influenced by _____.
A) periods of food availability
B) periods of daylight and darkness
C) magnetic fields
D) lunar cycles
Which of the following pairs are the best examples of homologous structures?
A) bones in the bat wing and bones in the human forelimb
B) owl wing and hornet wing
C) bat wing and bird wing
D) eyelessness in the Australian mole and eyelessness in the North American mole
The goal of restoration ecology is to _____.
A) replace a ruined ecosystem with a more suitable ecosystem for that area
B) return degraded ecosystems to a more natural state
C) manage competition between species in human-altered ecosystems
D) prevent further degradation by protecting an area with park status
Gene S controls the sharpness of spines in a type of cactus. Cactuses with the dominant
allele, S, have sharp spines, whereas homozygous recessive ss cactuses have dull
spines. At the same time, a second gene, N, determines whether or not cactuses have
spines. Homozygous recessive nn cactuses have no spines at all. If doubly heterozygous
SsNn cactuses were allowed to self-pollinate, the F2 would segregate in which of the
following ratios?
A) 3 sharp-spined:1 spineless
B) 1 sharp-spined:2 dull-spined:1 spineless
C) 1 sharp-spined:1 dull-spined:1 spineless
D) 9 sharp-spined:3 dull-spined:4 spineless
Which of the following are primarily responsible for cytokinesis in plant cells but not in
animal cells?
A) kinetochores
B) Golgi-derived vesicles
C) actin and myosin
D) centrioles and centromeres
As an undergraduate research assistant, your duties involve measuring water potential
in experimental soil-plant-atmosphere systems. Assume you make a series of
measurements in a system under normal daylight conditions, with stomata open and
photosynthesis occurring. Which of the following correctly depicts the trend your
measurement data should follow if the cohesion-tension mechanism is operating?
A) ψsoil < ψroots = ψleaves < ψatmosphere
B) ψatmosphere < ψleaves = ψroots < ψsoil
C) ψsoil < ψroots < ψleaves < ψatmosphere
D) ψatmosphere < ψleaves < ψroots < ψsoil
Two groups of tomatoes were grown under laboratory conditions, one with humus
added to the soil and one a control without humus. The leaves of the plants grown
without humus were yellowish (less green) compared with those of the plants grown in
the humus-enriched soil. The best explanation for this difference is that_____.
A) the healthy plants used the food in the decomposing leaves of the humus for energy
to make chlorophyll
B) the humus made the soil more loosely packed, so water penetrated more easily to the
roots
C) the humus contained minerals such as magnesium and iron, needed for the synthesis
of chlorophyll
D) the heat released by the decomposing leaves of the humus caused more rapid growth
and chlorophyll synthesis
An organism that lacks integration centers _____.
A) cannot receive stimuli
B) will not have a nervous system
C) will not be able to interpret stimuli
D) can be expected to lack myelinated neurons
How is plant cell cytokinesis different from animal cell cytokinesis?
A) The contractile filaments found in plant cells are structures composed of
carbohydrates; the cleavage furrow in animal cells is composed of contractile
phospholipids.
B) Plant cells deposit vesicles containing cell-wall building blocks on the metaphase
plate; animal cells form a cleavage furrow.
C) The structural proteins of plant cells separate the two cells; in animal cells, a cell
membrane separates the two daughter cells.
D) Plant cells divide after metaphase but before anaphase; animal cells divide after
anaphase.
Which of the following, when taken up by a cell, binds to a repressor so that the
repressor no longer binds to the operator?
A) inducer
B) promoter
C) repressor
D) corepressor
Two species of frogs belonging to the same genus occasionally mate, but the embryos
stop developing after a day and then die. These two frog species separate by _____.
A) reduced hybrid viability
B) hybrid breakdown
C) reduced hybrid fertility
D) gametic isolation
The questions below refer to the following description and figure.
The figure below represents a cross section of the sea floor through a mid-ocean rift
valley, with alternating patches of black and white indicating sea floor with reversed
magnetic polarities. At the arrow labeled “I” (the rift valley), the igneous rock of the sea
floor is so young that it can be accurately dated using carbon-14 dating. At the arrow
labeled “III,” however, the igneous rock is about one million years old, and
potassium-40 dating is typically used to date such rocks. Note: The horizontal arrows
indicate the direction of sea-floor spreading, away from the rift valley.
Which section of sea-floor crust should have the thickest layer of overlying sediment,
assuming a continuous rate of sediment deposition?
A) A
B) B
C) D
D) E
Nematodes and arthropods both _____.
A) develop an anus from the blastopore (pore) formed in the gastrula stage
B) are suspension feeders
C) grow by shedding their exoskeleton
D) have ciliated larvae
Folic acid supplements have become especially important for pregnant women because
_____.
A) folic acid supplies vitamins that only pregnant women can use
B) the fetus makes high levels of folic acid
C) folic acid deprivation is associated with neural tube abnormalities in a fetus
D) folic acid deprivation is a cause of heart abnormalities in a newborn
Which molecule shown above can function as a base?
A) A
B) B
C) C
D) D
A patient complaining of watery, itchy eyes and sneezing after being given a flower
bouquet as a birthday gift should first be treated with _____.
A) a vaccine
B) sterile pollen
C) antihistamines
D) monoclonal antibodies
What major benefits do plants and mycorrhizal fungi receive from their symbiotic
relationship?
A) Plants receive enzymes, and fungi receive nitrogen and phosphorus.
B) Plants receive increased root surface area, and fungi receive digestive enzymes.
C) Fungi receive photosynthetic products in exchange for living in plant root nodules.
D) Plants receive nitrogen and phosphorus, and fungi receive photosynthetic products.
Use the following diagram of a hypothetical food web to answer the question(s) below.
The arrows represent the transfer of energy between the various trophic levels.
Which letter represents an organism that could be a producer?
A) A
B) B
C) D
D) E
With regard to the destruction of tropical forests, the focus is often on biodiversity and
the impact to these ecosystems. What is a direct benefit to humans that helps explain
why these forests need to be preserved?
A) This diversity could contain undocumented insect species.
B) Natural and undisturbed areas are important wildlife habitats.
C) The diversity could contain novel drugs for consumers.
D) The plant diversity provides shade, which lowers global warming.