Stem cell transplants may someday be used to treat Parkinson’s disease. Researchers are
hopeful that these cells would alleviate the symptoms of Parkinson’s disease by _____.
A) preventing temporal lobe seizures
B) repairing sites of traumatic brain injury
C) replenishing missing ion channels
D) secreting the neurotransmitter dopamine
Based on cladistics, which eukaryotic kingdom is polyphyletic and, therefore,
unacceptable?
A) Plantae
B) Fungi
C) Animalia
D) Protista
Three-spined stickleback fish (Gasterosteus aculeatus) show substantial heritable
variation in gill-raker length related to differences in their diets. Longer gill rakers
appear to function better for capturing open-water prey, while shorter gill rakers
function better for capturing shallow-water prey. Which of the following types of
selection is most likely to be found in a large lake (open water in the middle and
shallow water around the sides) with a high density of these fish?
A) directional selection
B) stabilizing selection
C) disruptive selection
D) sexual selection
In his transformation experiments, what did Griffith observe?
A) Mixing a heat-killed pathogenic strain of bacteria with a living nonpathogenic strain
can convert some of the living cells into the pathogenic form.
B) Mixing a heat-killed nonpathogenic strain of bacteria with a living pathogenic strain
makes the pathogenic strain nonpathogenic.
C) Infecting mice with nonpathogenic strains of bacteria makes them resistant to
pathogenic strains.
D) Mice infected with a pathogenic strain of bacteria can spread the infection to other
mice.
Which of the following studies would shed light on the mechanism of spread of H5N1
virus from Asia?
A) Perform cloacal or saliva smears of migrating waterfowl to monitor whether any
infected birds show up in Alaska.
B) Test fecal samples for H5N1 in Asian waterfowl that live near domestic poultry
farms in Asia.
C) Test for the presence of H5N1 in poultry used for human consumption worldwide.
D) Locate and destroy birds infected with H5N1 in Asian open-air poultry markets.
You have isolated a previously unstudied protein, identified its complete structure in
detail, and determined that it catalyzes the breakdown of a large substrate. You notice it
has two binding sites. One of these is large, apparently the bonding site for the large
substrate; the other is small, possibly a binding site for a regulatory molecule. What do
these findings tell you about the mechanism of this protein?
A) It is probably a structural protein that is involved in cell-to-cell adhesion.
B) It is probably an enzyme that works through allosteric regulation.
C) It is probably an enzyme that works through competitive inhibition.
D) It is probably a cell membrane transport protein”like an ion channel.
DDT was once considered a ‘silver bullet” that would permanently eradicate insect
pests. Instead, DDT is largely useless against many insects. Which of these would have
prevented this evolution of DDT resistance in insect pests?
A) All habitats should have received applications of DDT at about the same time.
B) The frequency of DDT application should have been higher.
C) None of the insect pests would have genetic variations that resulted in DDT
resistance.
D) DDT application should have been continual.
Members of two different species possess a similar-looking structure that they use in a
similar way to perform about the same function. Which of the following would suggest
that the relationship more likely represents homology instead of convergent evolution?
A) The two species live at great distance from each other.
B) The two species share many proteins in common, and the nucleotide sequences that
code for these proteins are almost identical.
C) The structures in adult members of both species are similar in size.
D) Both species are well adapted to their particular environments.
In which of the following organisms does blood flow from the pulmocutaneous
circulation to the heart before circulating through the rest of the body?
A) annelids
B) fishes
C) frogs
D) insects
Many songbirds breed in North America in the spring and summer and then migrate to
Central and South America in the fall. They spend the winter in these warmer areas,
where they feed and prepare for the spring migration north and another breeding
season. Two hypothetical species of sparrow, A and B, overwinter together in mixed
flocks in Costa Rica. In spring, species A goes to the east coast of North America, and
species B goes to the west coast. What can you say about the isolating mechanisms of
these two species?
A) They must have strong postzygotic isolating mechanisms to spend winter in such
close proximity.
B) They must have strong prezygotic isolating mechanisms to spend winter in such
close proximity.
C) Their winter habitat has no bearing on their degree of reproductive isolation.
D) Reinforcement must be occurring when they winter together.
The human X and Y chromosomes _____.
A) are both present in every somatic cell of males and females
B) are the same size and have the same number of genes
C) include genes that determine an individual’s sex
D) are called autosomes
If the cytoplasm of a cell is at pH 7, and the mitochondrial matrix is at pH 8, then the
concentration of H+ ions _____.
A) is 10 times higher in the cytoplasm than in the mitochondrial matrix
B) is 10 times higher in the mitochondrial matrix than in the cytoplasm
C) in the cytoplasm is 7/8 the concentration in the mitochondrial matrix
D) in the cytoplasm is 8/7 the concentration in the mitochondrial matrix
About twenty-five of the ninety-two natural elements are known to be essential to life.
Which four of these twenty-five elements make up approximately 96 percent of living
matter?
A) carbon, sodium, hydrogen, nitrogen
B) carbon, oxygen, phosphorus, hydrogen
C) oxygen, hydrogen, calcium, nitrogen
D) carbon, hydrogen, nitrogen, oxygen
Many flowering plants coevolve with specific pollinators. The Madagascar orchid has a
12-inch floral tube and is a reliable nectar source for the hawkmoth, which has a
correspondingly long proboscis (tongue). Which statement most accurately describes
how coevolution might have occurred for the hawkmoth and Madagascar orchid shown
here?
A) The hawkmoths that expended the most effort to reach the nectar would be the most
fit, and pass the longer tongue phenotype to their offspring.
B) Natural selection would favor orchids with nectar tubes just long enough to for an
insect with pollen to make contact. Hawkmoths whose tongue could reach the deep
tubes would be more fit.
C) Hawkmoths whose tongue was just long enough to obtain nectar, but not able to pick
up pollen would become the most fit in the population.
D) It is most likely that mutations that resulted in both the length of the orchid floral
tube and the length of the hawkmoth tongue occurred abruptly and simultaneously.
What is the primary function of stems?
A) Facilitation of gas exchange
B) Water absorption and movement
C) Maximization of photosynthesis by leaves
D) Reproduction
In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the
frequency of allele a is 0.2. What is the frequency of individuals that are heterozygous
for this allele?
A) 0.020
B) 0.04
C) 0.16
D) 0.32
An organism with a cell wall would most likely be unable to take in materials through
_____.
A) osmosis
B) active transport
C) phagocytosis
D) facilitated diffusion
Nitric oxide and epinephrine _____.
A) both function as neurotransmitters
B) both function as steroid hormones
C) bind the same receptors
D) both cause a reduction in the blood levels of glucose
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. The relationship
between genes S and N is an example of _____.
A) incomplete dominance
B) epistasis
C) pleiotropy
D) codominance
What kinds of molecules pass through a cell membrane most easily?
A) large and hydrophobic
B) small and hydrophobic
C) large polar
D) ionic
A woman who has blood type A positive has a daughter who is type O positive and a
son who is type B negative. Rh positive is a trait that shows simple dominance over Rh
negative. Which of the following is a possible phenotype for the father?
A) A negative
B) O negative
C) B positive
D) AB negative
Use the following information to answer the question(s) below.
A student encounters an animal embryo at the eight-cell stage. The four smaller cells
that comprise one hemisphere of the embryo seem to be rotated 45 degrees and to lie in
the grooves between larger, underlying cells.
If we were to separate these eight cells and attempt to culture them individually, then
what is most likely to happen?
A) All eight cells will die immediately.
B) Each cell may continue development, but only into a nonviable embryo that lacks
many parts.
C) Each cell may develop into a full-sized, normal embryo.
D) Each cell may develop into a smaller-than-average, but otherwise normal, embryo.
Refer to the following information to answer the question*s) below.
Fossils of Lystrosaurus, a dicynodont therapsid, are most common in parts of
modern-day South America, South Africa, Madagascar, India, South Australia, and
Antarctica. The animal apparently lived in arid regions, and was mostly herbivorous. It
originated during the mid-Permian period, survived the Permian extinction, and
dwindled by the late Triassic, though there is evidence of a relict population in Australia
during the Cretaceous period. Some dicynodonts had two large tusks, extending down
from their upper jaws. The tusks were not used for food gathering, and in some species
were limited to males. Food was gathered using an otherwise toothless beak. Judging
from the fossil record in sedimentary rocks, these pig-sized organisms were the most
common mammal-like reptiles of the Permian.
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
The nematode Caenorhabditis elegans _____.
A) is composed of about 1000 cells, in which the developmental origin of each cell has
been mapped
B) has only a single chromosome, which has been fully sequenced
C) has about 1000 genes, each of which has been fully sequenced
D) uniquely, among animals, utilizes programmed cell death during normal
development
Which of the following is a FALSE statement concerning amino groups? Amino groups
_____.
A) are basic with respect to pH
B) are found in amino acids
C) contain nitrogen
D) are nonpolar
In most fungi, karyogamy does not immediately follow plasmogamy, which
consequently _____.
A) means that sexual reproduction can occur in specialized structures
B) results in multiple diploid nuclei per cell
C) allows fungi to reproduce asexually most of the time
D) results in heterokaryotic or dikaryotic cells
The agouti is most directly involved with the Brazil nut tree’s dispersal of _____.
A) male gametophytes
B) female gametophytes
C) sporophyte embryos
D) sporophyte megaspores
Which of the following examples of an ecological effect leading to an evolutionary
effect is most correct?
A) When seeds are not plentiful, trees produce more seeds.
B) A few individuals with denser fur survive the coldest days of an ice age, and the
reproducing survivors of the ice age will likely have more dense fur.
C) Fish that swim the fastest in running water catch the most prey and more easily
escape predation.
D) The insects that spend the most time exposed to sunlight have the most mutations.
The vast number and variety of flower species is probably related to various kinds of
_____.
A) seed dispersal agents
B) pollinators
C) herbivores
D) climatic conditions
The vascular bundle in the shape of a single central cylinder in a root is called the
_____.
A) cortex
B) stele
C) periderm
D) pith
Use the following information to answer the question(s) below.
Two populations of birds with somewhat different coloration live on opposite sides of a
peninsula. The habitat between the populations is not suitable for these birds. When
birds from the two populations are brought together, they produce young whose
appearance is intermediate between the two parents. These offspring will breed with
each other or with birds from either parent population, and all offspring of these
pairings appear intermediate to various degrees.
The two populations are _____.
A) different subspecies, under the morphological species concept
B) different species, under the biological species concept
C) different species, under the phylogenetic species concept
The greatest distance among the three genes is between a and c. What does this mean?
A) Gene c is between a and b.
B) Genes are in the order: abc.
C) Gene a is not recombining with c.
D) Gene a is between b and c.
The telencephalon region of the developing brain of a mammal _____.
A) divides further into the metencephalon and myelencephalon
B) develops from the midbrain
C) is the brain region most like that of ancestral vertebrates
D) gives rise to the cerebrum