50) The most important factors in determining primary productivity in the ocean are:
a. Temperature and nutrients.
b. Temperature and light.
c. Salinity and nutrients.
d. Light and nutrients.
e. Salinity and light.
51) Select the statement about energy flow that is false:
a. Secondary productivity declines with each trophic level.
b. Only net primary productivity is available to consumers.
c. About 90% of the energy at one trophic level does not appear at the next.
d. Eating meat is probably the most efficient way of acquiring the energy of
e. Only about one-thousandth of the chemical energy fixed by photosynthesis actually
reaches a tertiary (4th
) level consumer.
52) Many homeowners mow their lawns, collect the clippings and dispose of them in
landfills. Which of the following alternatives would disturb local ecosystems the least:
a. Do not mow the lawn; have sheep graze on it and put the sheep’s feces into the landfill.
b. Collect the clippings and burn them.
c. Either collect the clippings and add them to a compost pile, or don’t collect the
clippings and let them decompose in the lawn.
d. Collect the clippings and wash them into the nearest sewer that feeds into the local
e. Dig up the lawn and cover the yard with asphalt.
53) Not a way carbon is released to the atmosphere:
a. Primary production.
b. Cellular respiration.
c. Burning of fossil fuels.
d. Burning of forests.
e. Methane production by ruminants.
54) Select the statement about the nitrogen cycle that is false:
a. Plants can incorporate nitrogen directly from the atmosphere.
b. Nitrogen can be converted by lightning into a form that organisms can use.
c. Bacteria can convert atmospheric nitrogen into ammonium and nitrates.
d. Bacteria can convert ammonium and nitrates into atmospheric nitrogen.
e. Decomposers can convert proteins into ammonium and nitrates.
55) To recycle nutrients, the minimum an ecosystem must have is:
b. Producers and decomposers.
d. Producers, primary consumers, and decomposers. 9
e. Primary consumers and decomposers.
56) Which of the following would not qualify as an ecosystem service?
a. Prevention of erosion.
b. Decomposition of animal carcasses.
c. Moderation of weather extremes.
d. Aesthetic beauty.
e. None of the above
57) Intracellular molecular clocks are composed of genes and proteins that make up a
a. positive feedback loop
b. negative feedback loop
c. positive feedforward loop
d. negative feedforward loop
e. none of the above
58) Familial Advanced Sleep Phase Syndrome is a disorder that affects
a. circadian rhythms in Drosophila
b. learning and memory in Drosophila
c. circadian rhythms in humans
d. learning and memory in humans
e. all of the above
59) Which of the following is most likely to be a gene involved in circadian rhythms in
c. adenylate cyclase
60) Which of the following is the most complete description of a circadian rhythm?
a. An event that occurs once every 24 hours
b. An event that occurs once every 24 hours even in complete darkness
c. An event that occurs once every 24 hours even in complete darkness in Drosophila
d. An event that occurs once every 24 hours even in complete darkness in a Drosophila
e. An event that occurs once every 24 hours even in complete darkness in a Drosophila
61) Learning and memory can be studied in Drosophila using:
a. Odors and water
b. Odors and sight
c. Odors and taste
d. Odors and electric shocks
e. None of the above
62) The reason for studying the relationship between genes and behavior in Drosophila is:
a. They have a relatively simple genome
b. Genetics allows an investigator to identify genes with no previous function
c. Many genes in Drosophila are conserved with humans 10
d. Drosophila display numerous predictable behaviors
e. All of the above
63) Which of the following best describes imprinting?
a. An animal making a print on a tree
b. An animal making a visible print on another animal of the same species
c. An animal making a visible print on an animal of a different species
d. An animal learning something
e. An animal learning something at a specific time of its life
64) Which of the following best describes habituation?
a. Losing a response to a stimulus
b. Becoming extra responsive to a stimulus
c. Losing a response to a stimulus that was repetitively applied
d. Starting application of a repetitive stimulus
e. Stopping application of a repetitive stimulus
65) The animal phyla are defined on the basis of
a) unique developmental and body plans.
b) mitochondrial DNA sequence data.
c) DNA sequence data from nuclear genes.
d) DNA sequence data from chloroplasts.
e) DNA sequence data from all available sources.
66) Of the five phyla and subphyla listed, to which one are you most closely related?
67) The distal-less gene (dll) plays an important role in the development of all of the
following animal structures except:
a) insect antennae.
b) tetrapod forelimbs.
c) tetrapod hindlimbs.
e) echinoderm tube-feet.
68) Which one of the following groups of mammals lays eggs?
a) sea cows
c) sea horses
69) Of the following primate species or groups, which is most distantly related to humans?
d) Old world monkeys 11
70) Organisms that require molecular oxygen (O2) for growth
a) are always autotrophs.
b) are called aerobes.
c) are always chemoheterotrophs.
d) are known by the technical term as “breathers.”
e) are always photoheterotrophs.
71) The structure through which DNA is transferred from the donor cell to the recipient cell
during conjugation is called:
a) a transformer
b) a transducer
c) a pilus.
d) a mutator
e) a plasmid
72) Emphysema is a disease attributable almost entirely to smoking tobacco and is caused
primarily by damage to which component(s) of the normal lung:
d) a and b
e) none of the above
73) Muscles are joined to bones by
c. loose connective tissue.
d. Haversian systems.
e. positive feedback.
74) Given a glass of water and asked to raise the osmolarity of the water to the highest possible
value by adding one of the following materials, which would you add:
a) one gram of serum albumin.
b) one gram of sodium chloride
c) one gram of starch.
d) two grams of serum albumin.
e) half a gram of serum albumin.
75) The action potential
(a) can convey signals over long distances without decrement along the axon.
(b) can not result from integration of individual graded responses to synaptic inputs.
(c) is an electrical impulse which decays in amplitude as it propagates from the initiation zone
to the axon’s synaptic terminal.
(d) is a measure of the amount of transmitter stored at the axonal synaptic terminal.
(e) is an electrical impulse which changes dramatically in time course as it propagates along
76) The vertebrate cone photoreceptor response to light
(a) is in the form of action potentials whose rate is graded with light intensity. 12
(b) results in increasing the rate of release of synaptic transmitter.
(c) produces one transmitter molecule for each absorbed photon.
(d) is mediated by opening of chloride channels in the outer segment membrane.
(e) is a slow change in membrane potential graded with light intensity.
77) Which is true about skin
a) excellent barrier to bacterial penetration
b) covered with bacteria
c) prevents infections
d) tans easily
e) all of the above
78) Spaghnum is a moss that grows in bogs. Bogs are important because they
a. allow for rapid decomposition of organic matter.
b. function as a reservoir of the earth’s carbon. Loss of bog land would result in
increases of greenhouse gasses.
c. provide good aeration materials for soil mixes.
d. both a and b.
e. both b and c.
79) Hormones are able to maintain homeostasis because
a. they are not produced by exocrine glands.
b. they are present at low concentrations.
c. they may be found in the lymphatic system.
d. they are steroids.
e. they are subject to negative feedback.
80) Which hormone is a not a steroid?
81) If gastrulation did not occur,
a. fertilization would be blocked.
b. the blastula would not be formed.
c. the gastrula would not be formed.
d. cleavage would not occur in the zygote.
e. B and D would be the case.
82) Which one of the following mammals (arranged in size order) has the most yolk in its egg?
b. spiny echidna
e. There may be small differences in egg yolk content among the four species named above,
but because they are all mammals they all have almost no yolk in their eggs.
83) Which extraembryonic membrane of a chick embryo is used to store its waste products?
a. amnion 13
b. yolk sac
84) In humans, identical twins are possible because
a. the gray crescent divides the dorsal-ventral axis into new cells.
b. of interactions between extraembryonic cells and the zygote nucleus.
c. the blastomeres are genetically the same.
d. of the heterozygeneous distribution of cytoplasmic determinants in unfertilized eggs.
e. of convergent extension.
85) Plant stems bend towards light because:
A. All cells of stem elongate in response to auxin synthesis
B. Cells on the dark side of the stem preferentially elongate in response to auxin
C. Cells on the illuminated side of the stem preferentially elongate in response to auxin
D. Auxin causes inhibition of cell elongation
E. Cytokinin inhibits cell division on the dark side of the stem
86) Which of the plant hormone sets listed below all have growth enhancing properties?
A. Auxin, ethylene and GA
B. Cytokinin, GA and Abscisic Acid
C. Cytokinin, GA and Auxin
D. Ethylene, ABA, and GA
E. Auxin, Ethylene and ABA
87) The chemiosmotic model for polar auxin transport involves
A. A plasma membrane proton pump
B. An auxin carrier protein at the basal end of the cell
C. Ionized and uncharged forms of auxin
D. All of the above
E. None of the above
88) When the apical bud is removed from a plant, lateral branches begin the grow. The
phenomenon called “apical dominance” occurs in plants which have not had their apical buds
A. The apical bud produces cytokinin
B. The lateral buds produce auxin
C. Auxin made by apical buds inhibits lateral bud growth
D. Cytokinin produced by lateral buds overcomes GA inhibition.
E. None of the above
89) Mendel’s dwarf pea mutants can be restored to wild-type height by the application of GA, a
stem elongation hormone. The conclusion from this result is:
A. Mendel’s dwarf peas are defective in GA biosynthesis
B. Mendel’s dwarf peas are insensitive to GA
C. Mendel’s dwarf peas are able to degrade GA
D. Mendel’s dwarf peas are defective in GA responses.
E. None of above.
90) Plant seeds contain embryos that are alive but not growing. The hormone responsible for
suppressing the growth of the embryo is:
91) The transcription of a gene involved in the synthesis of a hormone is suppressed in transgenic
tomatoes. These tomatoes give rise to fruits that fail to ripen completely when left on the vine.
Ripening can be induced by treating the fruits with a gaseous hormone. This means the gene
inactivated in the transgenic plants encoded a protein involved in the synthesis of:
92) Plants can perceive changes in day-length, by measuring the length of night. Short day (long
night) plants flower only when grown in an 8 hr light/16 hr dark cycle. A red light pulse given in
the middle of the night disrupts flowering. A subsequent pulse of far-red light reverses the effect
of the red-light pulse. We conclude from these experiments that
A. the cryptochrome photoreceptor is involved in light perception
B. chlorophyll is involved in light control of flowering
C. phytochrome is the photoreceptor involved in control of flowering
D. All of the above
E. None of the above
93) Photosynthate made in leaves is transported to non photosynthetic tissues as:
94) The major driving force for the upward movement of water in the xylem is
B. solute potential
C. physical pressure from the cell wall
95) Plasma membrane ATPases are the driving force for a carrier- or channel-mediated uptake of
ions and large polar molecules. The plasma membrane ATPase acts by :
A. Pumping protons across the cell membrane to set up an membrane potential
B. Binding to solute and co-transporting with ATP
C. Binding to solute and co-transporting with protons
D. Facilitated diffusion
E. Passive diffusion
96) The water potential in a plant cell is equal to the: 15
A. Sum of the solute potential and pressure potential
B. Difference between the solute potential and pressure potential
C. Solute potential times the pressure potential
D. The solute potential divided by the pressure potential
E. The solute potential squared.
97) Ions and solutes can move from cell-to-cell via cytoplasmic connections called
plasmodesmata. This type of cell-to-cell transport is called:
98) Sucrose transport into phloem cells is called “phloem loading”. This term refers to the fact
that sucrose is transported into phloem cells
A. Along a concentration gradient
B. Against a concentration gradient
C. using symplastic connections
D. using K+ as a cotransported ion
E. None of the above
99) “Phloem unloading” refers to sucrose transport from the phloem into “sink” tissues such as
roots or potato tubers. Sucrose transport into the sink tissues occurs along a concentration
gradient and therefore occurs via a
A. xylem route
B. apoplastic route
C. transpiration route
D. symplastic route
E. cotransporter route
100) Stomata cells on the under surface of a leaf serve to regulate O2 and CO2 exchange and
transpiration. An influx of K+ into the stomata causes a:
A. decrease in the water potential and an influx of water
B. increase in water potential and an efflux of water
C. antiport of Na+
D. decrease in solute potential and an influx of water
E. decrease in solute potential and an efflux of water