The specific relationship between a legume and its mutualistic Rhizobium strain
probably depends on_____.
A) each legume having a chemical dialogue with a fungus
B) each Rhizobium strain having a form of nitrogenase that works only in the
appropriate legume host
C) each legume being found where the soil has only the Rhizobium specific to that
legume
D) specific recognition between the chemical signals and signal receptors of the
Rhizobium strain and legume species
A P. bursaria cell that has lost its zoochlorellae is aposymbiotic. If aposymbiotic cells
have population growth rates the same as those of healthy, zoochlorella-containing P.
bursaria in well-lit environments with plenty of prey items, then such an observation
would be consistent with which type of relationship?
A) parasitic
B) commensalistic
C) toxic
D) mutualistic
Researchers discovered that a new strain of bacteria that cause tuberculosis (M.
tuberculosis) taken from a dead patient has a point mutation in the rpoB gene that codes
for part of the RNA polymerase enzyme. This mutant form of RNA polymerase does
not function as well as the more common form of RNA polymerase. A commonly used
antibiotic called rifampin does not affect the mutant rpoB bacteria.
A researcher mixes M. tuberculosis with and without the rpoB mutation and adds the
bacteria to cell cultures. Half the cell cultures contain only standard nutrients, while the
other half of the cell cultures contain rifampin and the standard nutrients. After many
cell generations, the researcher finds that _____.
A) very few M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene
mutation, but almost all of the M. tuberculosis in the cell cultures with rifampin carry
the rpoB mutation
B) almost all M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene
mutation, but very few of the M. tuberculosis in the cell cultures with rifampin carry the
rpoB mutation
C) very few M. tuberculosis in any of the cell cultures carry the rpoB gene mutation
D) almost all of the M. tuberculosis in both types of cell cultures carry the rpoB
mutation
Among mammals, the male and female genital structures that consist mostly of erectile
tissue include the _____.
A) penis and clitoris
B) vas deferens and oviduct
C) testes and ovaries
D) prostate and ovaries
A plant that grows one year, dies back, and then grows again the following year,
produces flowers and then dies would be considered _____.
A) annual
B) biennial
C) perennial
D) not very fit
Graph (b) in the figure above shows the normal fluctuations of a population of grouse.
Assuming graph (a) in the figure above is the result of some experimental treatment in
the grouse population, what can be concluded?
A) The experimental treatment exacerbated the population cycling.
B) The experimental treatment did not affect population cycling in this species.
C) The experimental treatment has most likely identified the cause of population
cycling.
D) None of the other responses is true.
A hypothetical bacterium swims among human intestinal contents until it finds a
suitable location on the intestinal lining. It adheres to the intestinal lining using a
feature that also protects it from phagocytes, bacteriophages, and dehydration. Fecal
matter from a human in whose intestine this bacterium lives can spread the bacterium,
even after being mixed with water and boiled. The bacterium is not susceptible to the
penicillin family of antibiotics. It contains no plasmids and relatively little
peptidoglycan.
This bacterium’s ability to survive in a human who is taking penicillin pills may be due
to the presence of _____.
1. penicillin-resistance genes
2. a secretory system that removes penicillin from the cell
3. a Gram-positive cell wall
4. a Gram-negative cell wall
5. an endospore
A) 1 or 5
B) 2 or 3
C) 4 or 5
D) 2, 4, or 5
How might a single base substitution in the sequence of a gene affect the amino acid
sequence of a protein encoded by the gene, and why?
A) Only a single amino acid could change, because the reading frame is unaffected.
B) The amino acid sequence would be substantially altered, because the reading frame
would change with a single base substitution.
C) All amino acids following the substitution would be affected, because the reading
frame would be shifted.
D) It is not possible for a single base substitution to affect protein structure, because
each codon is three bases long.
Transgenic mice are useful to human researchers because they _____.
A) can be valuable animal models of human disease
B) are essential for mapping human genes
C) are now used in place of bacteria for cloning human genes
D) were instrumental in pinpointing the location of the huntingtin gene
A researcher has developed two stains for use with seed plants. One stains sporophyte
tissue blue; the other stains gametophyte tissue red. If the researcher exposes pollen
grains to both stains, and then rinses away the excess stain, what should occur?
A) The pollen grains will be pure red.
B) The pollen grains will be pure blue.
C) The pollen grains will have red interiors and blue exteriors.
D) The pollen grains will have blue interiors and red exteriors.
Neurotransmitters affect postsynaptic cells by _____.
I) initiating signal transduction pathways in the cells
II) causing molecular changes in the cells
III) affecting ion-channel proteins
IV) altering the permeability of the cells
A) I and III
B) II and IV
C) III and IV
D) I, II, III, and IV
The eight climographs below show yearly temperature (line graph and left vertical axis)
and precipitation (bar graph and right vertical axis) averages for each month for some
locations on Earth.
Which climograph shows the climate for location 5?
A) A
B) C
C) D
D) H
If a tunicate’s pharyngeal gill slits were suddenly blocked, the animal would have
trouble _____.
A) respiring
B) feeding
C) moving
D) respiring and feeding
The legless condition that is observed in several groups of extant reptiles is the result of
_____.
A) their common ancestor having been legless
B) a shared adaptation to an arboreal (living in trees) lifestyle
C) several instances of the legless condition arising independently of each other
D) individual lizards adapting to a fossorial (living in burrows) lifestyle during their
lifetimes
The osmoregulatory process called secretion refers to the _____.
A) reabsorption of nutrients from a filtrate
B) selective elimination of excess ions and toxins from body fluids
C) formation of an osmotic gradient along an excretory structure
D) expulsion of urine from the body
Use the following information to answer the question(s) below.
Researchers studying a small milkweed population note that some plants produce a
toxin and other plants do not. They identify the gene responsible for toxin production.
The dominant allele (T) codes for an enzyme that makes the toxin, and the recessive
allele (t) codes for a nonfunctional enzyme that cannot produce the toxin.
Heterozygotes produce an intermediate amount of toxin. The genotypes of all
individuals in the population are determined (see chart) and used to determine the actual
allele frequencies in the population.
Refer to the figure above. Is this population in Hardy-Weinberg equilibrium?
A) Yes.
B) No; there are more heterozygotes than expected.
C) No; there are more homozygotes than expected.
D) More information is needed to answer this question.
Which one of the following is LEAST likely to be a hotspot for birds?
A) Amazon River basin
B) East Africa
C) Southwest China
D) Greenland
Which structure is correctly paired with its tissue system?
A) root hair vascular tissue
B) guard cell vascular tissue
C) companion cell ground tissue
D) tracheid vascular tissue
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.
At puberty, an adolescent female body changes in both structure and function of several
organ systems, primarily under the influence of changing concentrations of estrogens
and other steroid hormones. How can one hormone, such as estrogen, mediate so many
effects?
A) Estrogen is produced in very large concentration by nearly every tissue of the body.
B) Each cell responds in the same way when steroids bind to the cell surface.
C) Estrogen is kept away from the surface of any cells not able to bind it at the surface.
D) Estrogen binds to specific receptors inside many kinds of cells, each with different
responses.
Which of the following plant growth responses is primarily due to the action of auxins?
A) leaf abscission
B) cell division
C) the detection of photoperiod
D) phototropism
Arrange the following in order from most general to most specific.
1 natural selection
2. microevolution
3. intrasexual selection
4. evolution
5. sexual selection
A) 4, 1, 2, 3, 5
B) 4, 2, 1, 3, 5
C) 4, 2, 1, 5, 3
D) 1, 4, 2, 5, 3
Bottlenose dolphins breathe air but can sleep in the ocean because _____.
A) they sleep for only thirty minutes at a time, which is the maximum interval they can
cease breathing
B) they fill their swim bladder with air to keep their blowholes above the surface of the
water while they sleep
C) they move to shallow water to sleep, so they do not need to swim to keep their
blowholes above the surface of the water
D) they alternate which half of their brain is asleep and which half is awake
Which of the three types of viruses shown above would you expect to include a
capsid(s)?
A) I only
B) II only
C) III only
D) I, II, and III
A gene for the MN blood group has codominant alleles M and N. If both children are of
blood type M, which of the following is possible?
A) Each parent is either M or MN.
B) Each parent must be type M.
C) Both children are heterozygous for this gene.
D) Neither parent can have the N allele.
The relationship between the insect hormones ecdysteroid and PTTH is an example of
_____.
A) an interaction of the endocrine and nervous systems
B) competitive inhibition of a hormone receptor
C) how peptide-derived hormones have more widespread effects than steroid hormones
D) homeostasis maintained by antagonistic hormones
Which of the following amino acids are most frequently phosphorylated by protein
kinases in the cytoplasm during signal transduction?
A) tyrosines
B) glycine and histidine
C) serine and threonine
D) glycine and glutamic acid
Male frogs give calls that attract female frogs to approach and mate. Researchers
examined mating calls of closely related but separate species of tree frogs in South
America. What outcomes could possibly occur where the ranges of two species
overlap?
I) The species will interbreed, eventually fusing over time.
II) A stable hybrid zone will form if hybrids are better adapted to the area of overlap
than either parent species is.
III) Species will continue to diverge and be isolated by behavioral or genetic
mechanisms.
A) I
B) II
C) III
D) I, II, and III
Which of the following is primarily responsible for limiting the number of trophic
levels in most ecosystems?
A) Many primary and higher-order consumers are opportunistic feeders.
B) Decomposers compete with higher-order consumers for nutrients and energy.
C) Nutrient cycling rates tend to be limited by decomposition.
D) Energy transfer between trophic levels is usually less than 20 percent efficient.
If a Drosophila female has a homozygous mutation for a maternal effect gene, _____.
A) she will not develop past the early embryonic stage
B) all of her offspring will show the mutant phenotype, regardless of their genotype
C) only her male offspring will show the mutant phenotype
D) only her female offspring will show the mutant phenotype