Predict the effects of a drug that increases adrenocorticotropic hormone (ACTH)
synthesis.
A) increase in glucocorticoid production
B) increase in release of corticotropin-releasing hormone (CRH)
C) decrease in cortisol release
D) decrease in release of corticotropin-releasing hormone (CRH)
You sample a population of butterflies and find that 56% are heterozygous at a
particular locus. What should be the frequency of the recessive allele in this population?
A) 0.08
B) 0.09
C) 0.70
D) Allele frequency cannot be determined from this information.
Fruit-fly eyes are of the compound type, which is structurally very different from the
camera-type eyes of mammals. Even the camera-type eyes of molluscs, such as octopi,
are structurally quite different from those of mammals. Yet, fruit flies, octopi, and
mammals possess very similar versions of Pax-6. The fact that the same gene helps
produce very different types of eyes is most likely due to _____.
A) the few differences in nucleotide sequence among the Pax-6 genes of these
organisms
B) variations in the number of Pax-6 genes among these organisms
C) the independent evolution of this gene at many different times during animal
evolution
D) differences in the control of Pax-6 expression among these organisms
Elements found on the left side of the periodic table contain outer shells that are _____;
these elements tend to form _____ in solution.
A) almost empty; cations
B) almost empty; anions
C) almost full; cations
D) almost full; anions
In a humoral or antibody-mediated immune response, specific B cells are stimulated by
Helper T cells to transform into plasma cells that secrete antibodies. What would be an
important feature added to B cells In this transition process?
A) Duplication of specific gene sequences for the appropriate antibody.
B) Increased rough endoplasmic reticulum in order to have the surface area needed for
antibody production.
C) Duplication of lysosomes in order to store the antibodies before transport.
Codons are three-base sequences that specify the addition of a single amino acid. How
do eukaryotic codons and prokaryotic codons compare?
A) Prokaryotic codons usually contain different bases than those of eukaryotes.
B) Prokaryotic codons usually specify different amino acids than those of eukaryotes.
C) The translation of codons is mediated by tRNAs in eukaryotes, but translation
requires no intermediate molecules such as tRNAs in prokaryotes.
D) Codons are a nearly universal language among all organisms.
Refer to the treatments listed below to answer the following question(s).
You isolate an infectious substance capable of causing disease in plants, but you do not
know whether the infectious agent is a bacterium, virus, viroid, or prion. You have four
methods at your disposal to analyze the substance and determine the nature of the
infectious agent.
I. Treat the substance with enzymes that destroy all nucleic acids and then determine
whether the substance is still infectious.
II. Filter the substance to remove all elements smaller than what can be easily seen
under a light microscope.
III. Culture the substance on nutritive medium, away from any plant cells.
IV. Treat the sample with proteases that digest all proteins and then determining
whether the substance is still infectious.
If you already know that the infectious agent was either a viroid or a prion, which
method(s) listed above would allow you to distinguish between these two possibilities?
A) I only
B) II only
C) IV only
D) either I or IV
The product of the p53 gene _____.
A) inhibits the cell cycle
B) slows down the rate of DNA replication by interfering with the binding of DNA
polymerase
C) causes cells to reduce expression of genes involved in DNA repair
D) allows cells to pass on mutations due to DNA damage
Looking at the figure above, what can be said about edge effects?
A) Biomass declines along edges of forest fragments.
B) Biomass increases along the edges of forest fragments.
C) Species diversity decreases along the edges of forest fragments.
D) Fragmentation does not affect biomass.
Arthropods invaded land about 100 million years before vertebrates did so. This most
clearly implies that _____.
A) arthropods evolved before vertebrates did
B) extant terrestrial arthropods are better adapted to terrestrial life than are extant
terrestrial vertebrates
C) vertebrates evolved from arthropods
D) arthropods have had more time to coevolve with land plants than have vertebrates
Which of the following cells transport sugars over long distances?
A) parenchyma cells
B) sclerenchyma cells
C) tracheids and vessel elements
D) sieve-tube elements
The first cloned cat, called Carbon Copy, was a calico, but she looked significantly
different from her female parent because _____.
A) the cloning was done poorly and it was likely that some contaminating cat DNA
became part of Carbon Copy’s genome
B) fur color genes in cats is determined by differential acetylation patterns
C) cloned animals have been found to have a higher frequency of transposon activation
D) X inactivation in the embryo is random and produces different patterns
Which chemical group can act as an acid?
A) amino
B) carbonyl
C) carboxyl
D) methyl
Motor proteins require which of the following to function in the movement of
chromosomes toward the poles of the mitotic spindle?
A) intact centromeres
B) a microtubule-organizing center
C) ATP as an energy source
D) synthesis of cohesin
A pregnant woman comes into the hospital past her due date. The doctor decides it is
time for the baby to be delivered. Before performing a cesarean section, the doctor
wants to try to induce labor. Which of the following would she most likely inject?
A) progesterone
B) luteinizing hormone (LH)
C) follicle-stimulating hormone (FSH)
D) oxytocin
Which of the following does not occur in prokaryotic gene expression, but does occur
in eukaryotic gene expression?
A) mRNA, tRNA, and rRNA are transcribed.
B) RNA polymerase binds to the promoter.
C) A cap is added to the end of the mRNA.
D) RNA polymerase requires a primer to elongate the molecule.
A gene that contains introns can be made shorter (but remain functional) for genetic
engineering purposes by using _____.
A) a restriction enzyme (endonuclease) to cut the gene into shorter pieces
B) reverse transcriptase to reconstruct the gene from its mRNA
C) DNA polymerase to reconstruct the gene from its polypeptide product
D) DNA ligase to put together fragments of the DNA that code for a particular
polypeptide
Auxins in plants are known to affect which of the following processes?
I) gravitropism of shoots
II) maintenance of seed dormancy
III) phototropism of shoots
IV) inhibition of lateral buds
V) apical dominance
A) only I and II
B) only I, III and V
C) only I, III, IV and V
D) only II, III, IV and V
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
If all individuals in the last remaining population of a particular bird species were all
highly related, which type of diversity would be of greatest concern when planning to
keep the species from going extinct?
I ) genetic diversity
II) species diversity
III) ecosystem diversity
A) only I
B) only II
C) only III
D) only II and III
During metamorphosis, a tadpoles tail is reduced in size by the process of _____.
A) regeneration
B) apoptosis
C) oxidative phosphorylation
D) re-differentiation
The smallest cell structure that would most likely be visible with a standard (not
super-resolution) research-grade light microscope is a _____.
A) mitochondrion
B) microtubule
C) ribosome
D) microfilament
Which statement about variation is true?
A) All phenotypic variation is the result of genotypic variation.
B) All genetic variation produces phenotypic variation.
C) All nucleotide variability results in neutral variation.
D) All new alleles are the result of nucleotide variability.
Which of the following can be effective in preventing the onset of viral infection in
humans?
A) taking vitamins
B) getting vaccinated
C) taking antibiotics
D) taking drugs that inhibit transcription
Parasitic species tend to have simple morphologies. Which of the following statements
best explains this observation?
A) Parasites are lower organisms, and this is why they have simple morphologies.
B) Parasites do not live long enough to inherit acquired characteristics.
C) Simple morphologies convey some advantage in most parasites.
D) Parasites have not yet had time to progress, because they are young evolutionarily.
One of the primary functions of RNA molecules is to _____.
A) transmit genetic information to offspring
B) function in the synthesis of proteins
C) make a copy of itself, thus ensuring genetic continuity
D) act as a pattern or blueprint to form DNA
A new species of aquatic chordate is discovered that closely resembles an ancient form.
It has the following characteristics: external armor of bony plates, no paired lateral fins,
and a suspension-feeding mode of nutrition. In addition to these, it will probably have
which of the following characteristics?
A) legs
B) no jaws
C) an amniotic egg
D) endothermy
Use the following information to answer the question(s) below.
Nudibranchs, a type of predatory sea slug, can have various protuberances (that is,
extensions) on their dorsal surfaces. Rhinophores are paired structures, located close to
the head, which bear many chemoreceptors. Dorsal plummules, usually located
posteriorly, perform respiratory gas exchange. Cerata usually cover much of the dorsal
surface and contain nematocysts at their tips.
Nudibranchs usually have two rhinophores. However, if they had a single rhinophore, it
could still carry out the function of two rhinophores, and with similar effectiveness, if
this single rhinophore _____.
A) had two branches, one directed to the left, the other to the right
B) was located within the mantle cavity
C) was as long as two rhinophores placed end to end
D) had cilia whose power strokes directed water away from the surface of the slug
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.
You have isolated DNA from three different cell types of the same organism,
determined the relative DNA content for each type, and plotted the results on the graph
shown in the figure below. Refer to the graph to answer the following question(s).
Which sample might represent an animal cell in the G2 phase of the cell cycle?
A) I
B) II
C) III
D) both I and II