The final step in a Sanger DNA sequencing reaction is to run the DNA fragments on a
gel. What purpose does this serve?
A) It adds ddNTP to the end of each DNA fragment.
B) It changes the length of the DNA fragments.
C) It separates DNA fragments based on their charge.
D) It separates DNA fragments generated during the sequencing reaction based on
one-nucleotide differences in their size.
Tetrodotoxin blocks voltage-gated sodium channels and ouabain blocks
sodium-potassium pumps. If you added both tetrodotoxin and ouabain to a solution
containing neural tissue, what responses would you expect?
A) immediate loss of resting potential
B) immediate loss of action potential with gradual loss of resting potential
C) slow decrease of resting potential and action potential amplitudes
D) No effect; the substances counteract each other.
You observe scrub jays hiding food and notice that one particular individual only
pretends to hide food. What kind of experiment could you perform to test whether this
behavior was random or in response to another signal?
A) Observe more of these behaviors in the wild and try to determine if the behavior is
random.
B) Hypothesize a set of signals that could produce this behavior and try to match the
behaviors with the signals.
C) Attempt to reproduce the behavior in captivity by using bird models and a computer
simulation.
According to our current knowledge of plant evolution, which group of organisms
should feature cell division most similar to that of land plants?
A) unicellular green algae
B) cyanobacteria
C) charophytes
D) red algae
A group of ten tomato plants are germinated and maintained in a large tray with no
drainage. After several weeks they all begin to wilt and die despite repeated watering
and fertilization. The most likely cause of this die-off is_____.
A) competition for resources
B) a lack of oxygen for the roots
C) organic nutrient depletion
D) no room left for root growth
The individual with genotype AaBbCCDdEE can make many kinds of gametes. Which
of the following is the major reason?
A) recurrent mutations forming new alleles
B) crossing over during prophase I
C) different possible assortment of chromosomes into gametes
D) the tendency for dominant alleles to segregate together
Which of the following molecules is the pentose sugar found in RNA?
A) 1
B) 6
C) 12
D) 13
Which of the following happens at the conclusion of meiosis I?
A) Homologous chromosomes of a pair are separated from each other.
B) The chromosome number per cell remains the same.
C) Sister chromatids are separated.
D) Four daughter cells are formed.
Connell conducted this experiment to learn more about _____.
A) character displacement in the color of barnacles
B) habitat preference in two different species of barnacles
C) how sea-level changes affect barnacle distribution
D) competitive exclusion and distribution of barnacle species
Use the following information to answer the question(s) below.
Giardia intestinalis is an intestinal parasite of humans and other mammals that causes
intestinal ailments in most people who ingest the cysts. Upon ingestion, each cyst
releases two motile cells, called trophozoites. These attach to the small intestine’s lining
via a ventral adhesive disk. The trophozoites anaerobically metabolize glucose from the
host’s intestinal contents to produce ATP. Reproduction is completely asexual, occurring
by longitudinal binary fission of trophozoites, with each daughter cell receiving two
haploid nuclei (n = 5). A trophozoite will often encyst as it passes into the large
intestine by secreting around itself a case that is resistant to cold, heat, and dehydration.
Infection usually occurs by drinking untreated water that contains cysts.
The mitosome of Giardia has no DNA within it. If it did contain DNA, then what
predictions should we be able to make about its DNA?
1. It is linear.
2. It is circular.
3. It has many introns.
4. It has few introns.
5. It is not associated with histone proteins.
6. It is complexed with histone proteins.
A) 1, 3, and 5
B) 1, 4, and 5
C) 2, 3, and 6
D) 2, 4, and 5
Why are changes in the global carbon cycle important?
I) Burning reduces available carbon for primary producers and, therefore, primary
consumers.
II) Deforestation and suburbanization reduce an area’s net primary productivity.
III) Increasing atmospheric concentrations of carbon dioxide could alter Earth’s climate.
IV) By using fossil fuels we are destroying a nonrenewable resource.
A) only I and III
B) only II and IV
C) only II, III, and IV
D) only I, II, III, and IV
In E. coli, to repair a thymine dimer by nucleotide excision repair, in which order do the
necessary enzymes act?
A) nuclease, DNA polymerase III, RNA primase
B) helicase, DNA polymerase I, DNA ligase
C) DNA ligase, nuclease, helicase
D) nuclease, DNA polymerase I, DNA ligase
In examining an unknown animal species during its embryonic development, how can
you be sure what you are looking at is a protostome and not a deuterostome?
A) There is evidence of cephalization.
B) The animal is triploblastic.
C) The animal is clearly bilaterally symmetrical.
D) You see a mouth, but not an anus.
The following questions refer to this table of codons.
A possible sequence of nucleotides in the template strand of DNA that would code for
the polypeptide sequence phe-leu-ile-val would be _____.
A) TTG-CTA-CAG-TAG
B) AUG-CTG-CAG-TAT
C) AAA-AAT-ATA-ACA
D) AAA-GAA-TAA-CAA
Polypeptides can have which of the following types of effects?
I) autocrine
II) paracrine
III) endocrine
A) only I and III
B) only II and III
C) only I and II
D) I, II, and III
Use the following description to answer the question(s) below.
In the ocean, on either side of the Isthmus of Panama, are thirty species of snapping
shrimp; some are shallow-water species, others are adapted to deep water. There are
fifteen species on the Pacific side and fifteen different species on the Atlantic side. The
Isthmus of Panama started rising about ten million years ago. The oceans were
completely separated by the isthmus about three million years ago.
In the following figure, the isthmus separates the Pacific Ocean on the left (side A)
from the Atlantic Ocean on the right (side B). The seawater on either side of the isthmus
is separated into five depth habitats (1-5), with 1 being the shallowest.
Why should deepwater shrimp on different sides of the isthmus have diverged from
each other earlier than shallow-water shrimp?
A) They have been geographically isolated from each other for a longer time.
B) Cold temperatures, associated with deep water, have accelerated the mutation rate,
resulting in faster divergence in deepwater shrimp.
C) The rise of the land bridge was accompanied by much volcanic activity. Volcanic ash
contains heavy metals, which are known mutagens. Ash fall caused high levels of heavy
metals in the ocean sediments underlying the deep water, resulting in accelerated
mutation rates and faster divergence in deepwater shrimp.
D) Fresh water entering the ocean from the canal is both less dense and cloudier than
seawater. The cloudy fresh water interferes with the ability of shallow-water shrimp to
locate mating partners, which reduces the frequency of mating, thereby slowing the
introduction of genetic variation.
Processing of filtrate in the proximal and distal tubules _____.
A) achieves the conversion of toxic ammonia to less toxic urea
B) maintains homeostasis of pH in body fluids
C) regulates the speed of blood flow through the nephrons
D) reabsorbs urea to maintain osmotic balance
Why do logged tropical rain forest soils typically have nutrient-poor soils?
A) Tropical bedrock contains little phosphorous.
B) Logging results in soil temperatures that are lethal to nitrogen-fixing bacteria.
C) Most of the nutrients in the ecosystem are removed in the harvested timber.
D) The cation exchange capacity of the soil is reversed as a result of logging.
Wernicke’s area _____.
A) is active when speech is heard and comprehended
B) is active during the generation of speech
C) coordinates the response to olfactory sensation
D) is found on the left side of the brain
The presence of a lophophore in a newly discovered species would suggest that the
species _____.
A) has an exoskeleton
B) grows by shedding its external covering
C) is motile
D) is a suspension feeder
A swim bladder is a gas-filled sac that helps fish maintain buoyancy. The evolution of
the swim bladder from lungs of an ancestral fish is an example of _____.
A) exaptation
B) changes in Hox gene expression
C) paedomorphosis
D) adaptive radiation
Use the following information to answer the question(s) below.
An otherwise healthy student in your class is infected with EBV, the virus that causes
infectious mononucleosis. The same student had already been infected when she was a
child, at which time she had merely experienced a mild sore throat and swollen lymph
nodes in her neck. This time, though infected, she does not get sick.
Which of the following is crucial to activation of the adaptive immune response?
A) memory cells
B) presentation of MHC (major histocompatibility complex)-antigen complex on a cell
surface
C) somatic hypermutation
D) phagocytosis of antibody-antigen complex by macrophages in the blood (the
humoral response)
Scientists interested in how populations interact within communities are attempting to
determine the species diversity of an island under study. What kind of data would be
most helpful to the scientists in determining diversity?
A) The number of different species on the island and the size of the population of each
species.
B) The number of species on the island that are consumers, producers, and
decomposers.
C) The relative biomass of each species on the island separated by trophic level.
D) The number of trophic levels on the island and the niche of each species.
Use the following information to answer the question(s) below.
Some plants have continually produced secondary defense compounds. Other plants are
induced to form secondary defense compounds when they are injured. Corn seedling
leaves that are chewed on by the caterpillars of a type of cutworm moth emit immediate
volatile chemicals (LOX products), and after six hours large amounts of terpenoid
compounds are released into the air. The terpenoids are released not only from the leaf
being chewed, but from all leaves of the plant. The terpenoid compounds attract a
parasitoid wasp female that lays her eggs on the caterpillar. When the wasp larvae
hatch, they eat and kill the moth caterpillar. (T.C.J. Turlings, J. H. Loughrin, P. J.
McCall, U. S. R. Rose, W. J. Lewis, and J. H. Tumlinson. 1995. How
caterpillar-damaged plants protect themselves by attracting parasitic wasps.
Proceedings of the National Academy of Sciences 92:4169-74.)
Refer to the paragraph on how caterpillar-damaged plants protect themselves by
attracting parasitic wasps. To test the hypothesis that caterpillar saliva and a wound are
both necessary to attract the parasitoid wasps you would need to include which of the
following in your experiment?
I) Slash the corn leaves with a razor blade.
II) Put caterpillar saliva on a leaf wound.
III) Put caterpillar saliva on an intact leaf.
A) only I
B) only II
C) only III
D) I, II, and III
Bonds between two atoms that are equally electronegative are _____.
A) hydrogen bonds
B) polar covalent bonds
C) nonpolar covalent bonds
D) ionic bonds
A population of plants experiences several years of severe drought. Much of the
population dies due to lack of water, but a few individuals survive. You set out to
discover the physiological basis for their adaptation to such an extreme environmental
change. You hypothesize that the survivors have the ability to synthesize higher levels
of _____ than their siblings do.
A) auxin
B) gibberellin
C) cytokinin
D) abscisic acid
Which of the following arise, directly or indirectly, from meristematic activity?
A) secondary xylem
B) leaves
C) dermal tissue
D) secondary xylem, leaves, dermal tissue, and tubers
After cytokinesis occurs in budding yeasts, the daughter cell has a _____.
A) similar nucleus and more cytoplasm than the mother cell
B) smaller nucleus and less cytoplasm than the mother cell
C) larger nucleus and less cytoplasm than the mother cell
D) similar nucleus and less cytoplasm than the mother cell
Use the following information to answer the question(s) below.
A large population of laboratory animals has been allowed to breed randomly for a
number of generations. After several generations, 25% of the animals display a
recessive trait (aa), the same percentage as at the beginning of the breeding program.
The rest of the animals show the dominant phenotype, with heterozygotes
indistinguishable from the homozygous dominants.
What proportion of the population is probably heterozygous (Aa) for this trait?
A) 0.05
B) 0.25
C) 0.50
D) 0.75
What would be the most direct effect of removing or damaging an insect’s antennae?
The insect would have trouble _____.
A) hearing
B) mating
C) seeing
D) smelling
Animals that have external fertilization are most likely to reproduce in which of the
following areas?
A) sand dune
B) polar ice sheet
C) shallow lake
D) tallgrass prairie
During elongation, which site in the ribosome represents the location where a codon is
being read?
A) E site
B) P site
C) A site
D) the small ribosomal subunit
Cells require which of the following to form cilia or flagella?
A) tubulin
B) laminin
C) actin
D) intermediate filaments