Whatever its ultimate cause(s), the Cambrian explosion is a prime example of _____.
A) mass extinction
B) evolutionary stasis
C) adaptive radiation
D) a large meteor impact
What must be true of any organ described as vestigial?
A) It must be analogous to some feature in an ancestor.
B) It must be homologous to some feature in an ancestor.
C) It must be both homologous and analogous to some feature in an ancestor.
D) It need be neither homologous nor analogous to some feature in an ancestor.
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 statements best summarizes the differences between DNA and
RNA?
A) DNA encodes hereditary information, whereas RNA does not.
B) The bases in DNA contain sugars, whereas the bases in RNA do not contain sugar.
C) DNA nucleotides contain a different sugar than RNA nucleotides.
D) DNA contains the base uracil, whereas RNA contains the base thymine.
Which of the following has both endocrine and exocrine activity?
A) the pituitary gland
B) parathyroid glands
C) salivary glands
D) the pancreas
A researcher is using adult stem cells and comparing them to other adult cells from the
same tissue. Which of the following is a likely finding?
A) The cells from the two sources exhibit different patterns of DNA methylation.
B) Adult stem cells have more DNA nucleotides than their counterparts.
C) The two kinds of cells have virtually identical gene expression patterns in
microarrays.
D) The nonstem cells have fewer repressed genes.
What is the advantage of having small, needlelike leaves?
A) increased transpiration rate
B) decreased transpiration rate
C) increased efficiency of light capture
D) decreased efficiency of light capture
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 only be a primary consumer?
A) A
B) B
C) C
D) D
Which of the following is in the correct order for one cycle of polymerase chain
reaction (PCR)?
A) Denature DNA; add fresh enzyme; anneal primers; add dNTPs; extend primers.
B) Anneal primers; denature DNA; extend primers.
C) Extend primers; anneal primers; denature DNA.
D) Denature DNA; anneal primers; extend primers.
A bone marrow transplant may not be appropriate from a given donor (Jane) to a given
recipient (Jane’s cousin Bob), even though Jane has previously given blood for one of
Bob’s needed transfusions, because _____.
A) even though Jane’s blood type is a match to Bob’s, her major histocompatability
(MHC) proteins may not be a match
B) a blood type match is less stringent than a match required for transplant because
blood is more tolerant of change
C) for each gene, there is only one blood allele but many tissue alleles
D) Jane’s MHC class II genes are not expressed in bone marrow
Suppose, while out camping in a forest, you found a chordate with a long, slender,
limbless body slithering across the ground near your tent. This critter could be _____.
A) a lampreys
B) a mammal
C) an amphibian
D) a skate
Lipids _____.
A) are insoluble in water
B) are made from glycerol, fatty acids, and nitrogen
C) contain less energy than proteins and carbohydrates
D) are made by dehydration reactions
Encouraging the growth (via nutrient fertilization) of photosynthetic protists in marine
environments may help reduce global warming because _____.
A) photosynthetic protists are primary consumers in many marine food chains
B) photosynthetic protists fix atmospheric carbon dioxide, decreasing atmospheric
carbon dioxide levels
C) the increased oxygen consumption by large populations of photosynthetic protists
will increase photosynthesis in land plants
D) photosynthetic protists would release a lot of oxygen, and fertilizing them would
increase levels of oxygen in the atmosphere
The functional significance of porous septa in certain fungal hyphae is most similar to
that represented by which pair of structures in animal cells and plant cells, respectively?
A) desmosomes tonoplasts
B) gap junctions plasmodesmata
C) tight junctions plastids
D) centrioles plastids
Innate immunity _____.
A) is activated immediately upon infection
B) depends on an infected animal’s previous exposure to the same pathogen
C) is based on recognition of antigens that are specific to different pathogens
D) is found only in vertebrate animals
The following table depicts characteristics of five prokaryotic species (A-E). Use the
information in the table to answer the question(s) below
Species D is pathogenic if it gains access to the human intestine. Which other species, if
it coinhabited a human intestine along with species D, is most likely to result in a
recombinant species that is both pathogenic and resistant to some antibiotics?
A) species A
B) species B
C) species C
D) species E
Which of the following would be considered an example of bioremediation?
A) adding nitrogen-fixing microorganisms to a degraded ecosystem to increase nitrogen
availability
B) using a bulldozer to regrade a strip mine
C) dredging a river bottom to remove contaminated sediments
D) adding seeds of a chromium-accumulating plant to soil contaminated by chromium
Jams, jellies, preserves, honey, and other foods with high sugar content hardly ever
become contaminated by bacteria, even when the food containers are left open at room
temperature. This is because bacteria that encounter such an environment ____.
A) undergo death as a result of water loss from the cell
B) are unable to metabolize the glucose or fructose, and thus starve to death
C) are obligate anaerobes
D) are unable to swim through these thick and viscous materials
At the summit of a high mountain, the atmospheric pressure is 380 mm Hg. If the
atmosphere is still composed of 21percent oxygen, then the partial pressure of oxygen
at this altitude is about _____.
A) 80 mm Hg
B) 160 mm Hg
C) 380 mm Hg
D) 760 mm Hg
Regardless of where in the world a vineyard is located, for the winery to produce a
Burgundy, it must use varietal grapes that originated in Burgundy, France. The most
effective way for a new California grower to plant a vineyard to produce Burgundy is
to_____.
A) plant seeds obtained from French varietal Burgundy grapes
B) transplant varietal Burgundy plants from France
C) acquire a tissue culture of varietal Burgundy grapes from France
D) graft varietal Burgundy grape scions onto native (Californian) root stocks
Radish flowers may be red, purple, or white. A cross between a red-flowered plant and
a white-flowered plant yields all-purple offspring. The part of the radish we eat may be
oval or long, with long being the dominant trait. If true-breeding red long radishes are
crossed with true-breeding white oval radishes, the F1 will be expected to be which of
the following?
A) red and long
B) white and long
C) purple and long
D) purple and oval
Loss of water from the aerial parts of plants is called _____.
A) dehydration
B) respiration
C) gas exchange
D) transpiration
It is estimated that animal-pollinated or insect-pollinated plants produce 1000 pollen
grains for each ovule; wind-pollinated plants produce 1,000,000 pollen grains for each
ovule. What does that indicate about pollination systems?
A) Wind-pollinated plants rarely produce seeds.
B) Wind pollination is more efficient than animal-assisted pollination.
C) Wind pollination is less efficient than animal-assisted pollination.
D) Wind pollination is costlier to the plant than animal-assisted pollination.
After finding a new medicinal plant, a pharmaceutical company decides to determine if
the plant has genes similar to those of other known medicinal plants. To do this, the
company annotates the genome of the new plant to _____.
A) determine what proteins are produced
B) determine what mRNA transcripts are produced
C) identify genes and determine their functions
D) identify the location of mRNA within the plant cells
The cells lining the air sacs in the lungs make up a _____.
A) simple squamous epithelium
B) stratified squamous epithelium
C) pseudostratified ciliated columnar epithelium
D) simple columnar epithelium
Sharks live in seawater. Their tissues are isotonic to seawater, but their concentrations
of sodium ions, potassium ions, and chloride ions in cells and extracellular fluids are
similar to those of freshwater fishes. How is that possible?
A) Urea and trimethylamine oxide contribute to intra- and extracellular osmolarity in
shark tissues.
B) Metabolic intermediates of sharks tie up intracellular chloride and potassium ions.
C) Their blood is hypotonic to their tissues.
D) They excrete large quantities of electrolytes.
The activity of acetylcholine in a synapse is terminated by its_____.
A) diffusion across the presynaptic membrane
B) active transport across the postsynaptic membrane
C) diffusion across the postsynaptic membrane
D) degradation on the postsynaptic membrane
Can the atomic mass of an element vary?
A) No, it is fixed. If it changes at all then you have formed a different element.
B) Yes. Adding or losing electrons will substantially change the atomic mass.
C) Yes. Adding or losing protons will change the atomic mass without forming a
different element.
D) Yes. Adding or losing neutrons will change the atomic mass without forming a
different element.
Which of the following illustrations is NOT a structural isomer of an organic compound
with the molecular formula C6H14? For clarity, only the carbon skeletons are shown;
hydrogen atoms that would be attached to the carbons have been omitted.
A)
B)
C)
D)
Which of the following is a widely supported explanation for the tendency of tropical
communities to have greater species diversity than temperate or polar communities?
A) There are fewer parasites to negatively affect the health of tropical communities.
B) Tropical communities are low in altitude, whereas temperate and polar communities
are high in altitude.
C) Tropical communities are generally older than temperate and polar communities.
D) More competitive dominant species have evolved in temperate and polar
communities.
In birds, sex is determined by a ZW chromosome scheme that is much like the typical
XY scheme seen in humans and many other organisms, except that the system is
reversed: Males are ZZ (similar to XX in humans) and females are ZW (similar to XY
in humans). A lethal recessive allele that causes death of the embryo occurs on the Z
chromosome in pigeons. What would be the sex ratio in the offspring of a cross
between a male heterozygous for the lethal allele and a normal female?
A) 1:1 male to female
B) 3:1 male to female
C) 1:2 male to female
D) 2:1 male to female
Which of the following best describes the significance of the TATA box in eukaryotic
promoters?
A) It is the recognition site for a specific transcription factor.
B) It sets the reading frame of the mRNA.
C) It is the recognition site for ribosomal binding.
D) Its significance has not yet been determined.
Nucleic acids are polymers made up of which of the following monomers?
A) nucleotides
B) sugars
C) amino acids
D) nitrogenous bases