What is true of the Cambrian explosion?
A) There are fossils of animals in geological strata that are older than the Cambrian
explosion.
B) Only the fossils of microorganisms are found in geological strata older than the
Cambrian explosion.
C) The Cambrian explosion is evidence for the instantaneous creation of life on Earth.
D) The Cambrian explosion marks the appearance of filter-feeding animals in the fossil
record.
What major advantage is conveyed by having a system of adaptive immunity?
A) It enables a rapid defense against an antigen that has been previously encountered.
B) It enables an animal to counter most pathogens almost instantly the first time they
are encountered.
C) It results in effector cells with specificity for a large number of antigens.
D) It allows for the destruction of antibodies.
The loss of water from a plant by transpiration cools the leaf. Movement of water in
transpiration requires both adhesion to the conducting walls and wood fibers of the
plant and cohesion of the molecules to each other. A scientist wanted to increase the rate
of transpiration of a crop species to extend its range into warmer climates. The scientist
substituted a nonpolar solution with an atomic mass similar to that of water for
hydrating the plants. What do you expect the scientist’s data will indicate from this
experiment?
A) The rate of transpiration will be the same for both water and the nonpolar substance.
B) The rate of transpiration will be slightly lower with the nonpolar substance as the
plant will not have evolved with the nonpolar compound.
C) Transpiration rates will fall to zero as nonpolar compounds do not have the
properties necessary for adhesion and cohesion.
D) Transpiration rates will increase as nonpolar compounds undergo adhesion and
cohesion with wood fibers more readily than water.
What is the major structural difference between starch and glycogen?
A) the types of monosaccharide subunits in the molecules
B) the type of glycosidic linkages in the molecule
C) whether glucose is in the α or β form
D) the amount of branching that occurs in the molecule
Map units on a linkage map cannot be relied upon to calculate physical distances on a
chromosome for which of the following reasons?
A) The frequency of crossing over varies along the length of the chromosome.
B) The relationship between recombination frequency and map units is different in
every individual.
C) Physical distances between genes change during the course of the cell cycle.
D) The gene order on the chromosomes is slightly different in every individual.
What is true about the genus Sphagnum?
A) It is an economically important liverwort.
B) It grows in extensive mats in grassland areas.
C) It accumulates to form coal and is burned as a fuel.
D) It is an important carbon sink, reducing atmospheric carbon dioxide.
The goal of restoration ecology is to _____.
A) replace a ruined ecosystem with a more suitable ecosystem for that area
B) return degraded ecosystems to a more natural state
C) manage competition between species in human-altered ecosystems
D) prevent further degradation by protecting an area with park status
What do we mean when we use the terms monohybrid cross and dihybrid cross?
A) A monohybrid cross involves a single parent, whereas a dihybrid cross involves two
parents.
B) A dihybrid cross involves organisms that are heterozygous for two characters that are
being studied, and a monohybrid cross involves organisms that are heterozygous for
only one character being studied.
C) A monohybrid cross is performed for one generation, whereas a dihybrid cross is
performed for two generations.
D) A monohybrid cross results in a 9:3:3:1 ratio whereas a dihybrid cross gives a 3:1
ratio.
Snake behavior in Wisconsin changes throughout the year. For example, a snake is
_____.
A) less active in winter because the food supply is decreased
B) less active in winter because it does not need to avoid predators
C) more active in summer because that is the period for mating
D) more active in summer because it can gain body heat by conduction
To recycle nutrients, an ecosystem must have, at a minimum, _____.
A) producers
B) producers and decomposers
C) producers, primary consumers, and decomposers
D) producers, primary consumers, secondary consumers, and decomposers
A phenotypically normal prospective couple seeks genetic counseling because the man
knows that he has a translocation of a portion of his chromosome 4 that has been
exchanged with a portion of his chromosome 12. Although his translocation is
balanced, he and his wife want to know the probability that his sperm will be abnormal.
What is your prognosis regarding his sperm?
A) 1/4 will carry the two normal chromosomes, 4 and 12, 1/4 will have only the two
translocation chromosomes and no normal chromosomes 4 and 12, and 1/2 will have
both normal and translocated chromosomes.
B) All will carry the same translocation as the father.
C) None will carry the translocation.
D) 1/2 will be normal and the rest will have the father’s translocation.
An animal cell lacking oligosaccharides on the external surface of its plasma membrane
would likely be impaired in which function?
A) transporting ions against an electrochemical gradient
B) cell-cell recognition
C) attaching the plasma membrane to the cytoskeleton
D) establishing a diffusion barrier to charged molecules
In E. coli, which enzyme catalyzes the elongation of a new DNA strand in the →
direction?
A) primase
B) DNA ligase
C) DNA polymerase III
D) helicase
In colorectal cancer, several genes must be mutated for a cell to develop into a cancer
cell. Which of the following kinds of genes would you expect to be mutated?
A) genes coding for enzymes that act in the colon
B) genes involved in control of the cell cycle
C) genes that are especially susceptible to mutation
D) genes of the bacteria, which are abundant in the colon
Lymph hearts are pumping structures that drive lymph through the lymphatic system,
returning it to the circulatory system at the large veins entering the heart. Researchers
examined rate and strength of pumping of lymph hearts in two species of amphibians, a
toad (Bufo marinus) and a frog (Rana catesbiana). During hemorrhage or dehydration,
the volume of blood in the circulatory system falls. (E. A. DeGrauw and S. S. Hillman.
2004. General function and endocrine control of the posterior lymph hearts in Bufo
marinus and Rana catesbiana. Physiological and Biochemical Zoology 77(4):594-600.)
If, during protein starvation, the osmotic pressure on the venous side of capillary beds
drops below the hydrostatic pressure, then _____.
A) hemoglobin will not release oxygen
B) fluids will tend to accumulate in tissues
C) the pH of the interstitial fluids will increase
D) plasma proteins will escape through the endothelium of the capillaries
What is the function of the osmotic gradient found in the kidney? The osmotic gradient
allows for _____.
A) electrolytes to move from low to high concentrations in the absence of ATP
B) the precise control of the retention of water and electrolytes
C) the loop of Henle to deliver water to the renal vein
D) the filtration of large cells at the glomerulus
Which of the following allows water to move much faster across cell membranes?
A) the sodium-potassium pump
B) ATP
C) peripheral proteins
D) aquaporins
According to the concept of punctuated equilibrium, _____.
A) natural selection is unimportant as a mechanism of evolution
B) given enough time, most existing species will gradually give rise to new species
C) a new species accumulates most of its unique features as it comes into existence
D) evolution of new species features long periods during which changes are occurring,
interspersed with short periods of equilibrium, or stasis
When an animal cell is placed in a hypotonic solution and water enters the cell via
osmosis, the volume of the cell increases until it bursts. This does not happen to plant
cells, because _____.
A) they have large central vacuoles, which provide abundant space for storage of
incoming water
B) they have cell walls, which prevent the entry of water by osmosis
C) they have cell walls, which provide pressure to counteract the pressure of the
incoming water
D) certain gated channel proteins embedded in their plasma membranes open as
osmotic pressure decreases, allowing excess water to leave the cell
Refer to the life cycles illustrated in the figure below to answer the following
question(s).
Which of the life cycles is typical for most fungi and some protists?
A) I only
B) II only
C) III only
D) I and II
Which of the following is a producer?
A) kinetoplastid
B) apicomplexan
C) diatom
D) ciliates
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.
Given its mode of reproduction and internal structures, which of the following should
be expected to occur in Giardia at some stage of its life cycle?
A) separation (segregation) of daughter chromosomes
B) crossing over
C) meiosis
In a hypothetical environment, fishes called pike-cichlids are visual predators of large,
adult algae-eating fish (in other words, they locate their prey by sight). The population
of algae-eaters experiences predatory pressure from pike-cichlids. Which of the
following is least likely to result in the algae-eater population in future generations?
A) selection for drab coloration of the algae-eaters
B) selection for nocturnal algae-eaters (active only at night)
C) selection for larger female algae-eaters, bearing broods composed of more, and
larger, young
D) selection for algae-eaters that become sexually mature at smaller overall body sizes
Based on the data in the figure above, which of the following statements is true?
A) Area 1 could be called a boreal forest/taiga.
B) Area 2 could be called a temperate grassland.
C) Area 1 could be called a tropical wet/rain forest.
D) Area 2 could be tundra.
Why do RNA viruses appear to have higher rates of mutation?
A) RNA nucleotides are more unstable than DNA nucleotides.
B) Replication of their genomes does not involve proofreading.
C) RNA viruses can incorporate a variety of nonstandard bases.
D) RNA viruses are more sensitive to mutagens.
The symplastic route can transport _____.
A) sugars, mRNA, and mitochondria
B) mRNA, mitochondria, and proteins
C) mitochondria, mRNA, and viruses
D) viruses, sugars, and mRNA
Which of the following statements about evolution of behavior is correct?
A) Natural selection will favor behavior that enhances survival and reproduction.
B) An animal may show behavior that minimizes reproductive fitness.
C) If a behavior is less than optimal, it will eventually become optimal through natural
selection.
D) Innate behaviors cannot be altered by natural selection.
Energy released by the electron transport chain is used to pump H+ into which location
in eukaryotic cells?
A) mitochondrial outer membrane
B) mitochondrial inner membrane
C) mitochondrial intermembrane space
D) mitochondrial matrix
Hutchinson-Gilford progeria is an exceedingly rare human genetic disorder in which
there is very early senility and death, usually from coronary artery disease, at an
average age of 13 years. Patients, who look very old even as children, do not live to
reproduce. Which of the following represents the most likely assumption?
A) The disease is autosomal dominant.
B) The disorder will increase in frequency in successive generations within a family.
C) The disorder may be due to mutation in a single protein-coding gene.
D) Each patient will have had at least one affected grandparent or parent.
A moth preparing for flight on a cold morning may warm its flight muscles via _____.
A) acclimatization
B) torpor
C) evaporative cooling
D) shivering thermogenesis
Exon shuffling occurs during _____.
A) splicing of DNA
B) DNA replication
C) meiotic recombination
D) translation
Because the foods eaten by animals are often composed largely of macromolecules,
animals need to have mechanisms for _____.
A) dehydration synthesis
B) enzymatic hydrolysis
C) regurgitation
D) demineralization