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1) What structure in the plant regulates transpiration of water into the environment?
A. Stomata
B. Cuticles
C. Trichomes
D. Sporangia
E. Mitochondra
2) Dicots differ from monocots in that
A.  in the stem, dicot veins are complex whereas monocot stems are arranged in a ring.
B.  in the leaf, dicot veins have netted venation whereas monocot stems have parallel venation.
C.  Dicot stems do not have vascular bundles, whereas monocot stems have vascular bundles.
D. Dicots usually have floral parts in multiples of three, whereas monocots have floral parts in
multiples of four or five.
3) A root hair is
A.  a continuous extension of a cell from the vascular tissue
B.  a specialized outward extension of a root epidermal cell
C.  The site of adventitious root formation
D.  The main site where the root apical meristem is found
4) Apical dominance is prevalent in many plant species.  It is caused  
A.  when a terminal bud sends signals to stimulate lateral bud growth, thus producing lateral
shoots dominant over the terminal shoot.
B.  when lateral buds send signals to the apex to grow.  Loss of the lateral buds will cause the
apex to stop growing.
C.  when signals from lateral roots inhibit growth of the primary root
D.  when the most mature trees in the canopy shade out neighboring trees and prevent their
E.  when the terminal bud sends signals to inhibit the growth of lateral shoots.  Loss of the
terminal bud results in growth of the lateral shoots.
5) In the vasculature of a plant, the phloem transports photosynthates and nutrients.  Phloem is
composed of these cell types
A.  vessels, fibers, parenchyma
B.  vessels, companion cells, and sieve-tube members
C.  companion cells, quiescent cells, and sieve-tube members
D.  sieve tube members and companion cells
6) In the growing primary root, three zones of growth are active. These are the
A.  zone of cell division, elongation and maturation
B.  zone of cell quiescence, enumeration and expansion
C.  zone of cell division, maturation and migration
D.  zone of cell elongation, maturation, and reversion.
7) In the lamina (blade) of the leaf, the palisade parenchyma is specialized for ______________
and the spongy parenchyma is most specialized for    ______________.
A.  water absorption……gas exchange
B.  photosynthesis……gas exchange
C.  gas exchange…….water absorption
D.  structural support……photosynthesis   2
8) According to the ABC theory of floral organ determination
A. A gene expression alone leads to formation of carpels.
B. B and C gene expression leads to the formation of carpels.
C. A and C gene expression leads to the formation of petals.
D. C gene expression alone leads to the formation of carpels.
9) The most abundant compound in plant walls is a molecule called cellulose.  Cellulose itself is
composed of a polymer of  
A.  sugar molecules.
B.  phenolic compounds.
C.  lipids.
D.  proteins.
10) Dr. Gerome Challenger discovered a new essential nutrient required for plant growth.  He
proved his remarkable discovery by
A.  adding this nutrient to the soil and noticing that the plants treated with this nutrient grew
better then the untreated plants.
B.  adding this nutrient to the soil and noticing that at low dose treatments the plants were healthy
and at high doses the plants died
C.  growing plants hydroponically and noticing that individuals without the nutrient did much
D.  growing plant hydroponically for several generations and noticing that eventually the plants
could not produce viable seeds without the nutrient.
11) The clay particles in the soil are important for plants because they
A. are composed of organic matter.
B. eliminate spaces for air and facilitate drainage.
C. carry a negative charge and therefore are a repository of positive ions.
D. allow positively charged ions to leach from soil following a rain.
E. are the basic building structures found in plant cell walls.
12) One step farmers can take towards sustainable agriculture can be obtained if
A.  topsoil is retained by contour planting
B.  nitrogen is provided with a heavy reliance on synthetic fertilizers
C.  the soil is continuously irrigated year after year.
D.  Cover crops are never planted.
13) Plants are able to fix N2 from the air by
A.  the use of a specialized chemical reaction using clay particles.
B.  the use of specialized tubes (pneumatophores) reaching from the roots to the atmosphere that
absorb gaseous nitrate.
C   the use of symbiotic nitrogen fixing bacteria that live in root nodules.
D.  the use of parasitic traps that collect N2  catalyzing insects.
14) A signal molecule that originates from the root hair and reaches rhizobium to initiate the
infection process is called a
A.  Nod factor
B.  chitin-like substance
C.  pectin
D.  flavonoid   3
15) Both ectomycorrhizea and endomicorrhizea effect plant growth
A.  in a negative fashion due to parasitic activity
B.  in a negative fashion due to the fungi’s consumption of valuable resources
C.  in a positive fashion due to the fungi’s ability to enhance the root’s absorption of minerals and
D.  in a positive fashion due to the fungi’s ability to provide photosynthetic products to the plants.
16) Epiphytic plants have
A.  a sophisticated root system adapted to absorb nutrients from the soil
B.  the ability to grow on the surface of other plants or structures
C.  depend on the photosynthetic production of food from their hosts for survival
D.  all have specialized structures to trap insects as a nitrogen supplement.
17) Arabidopsis was chosen as the first plant to have its genome completely sequenced because:
A.  it has a full set of chromosome
B.  it has an attractive, and popular horticultural flower found in gardens worldwide.
C.  it produces rare oils that may solve the world’s energy crises
D.  it has a small stature, a fast life cycle, simple genetics and a small genome.
18) The mature seed produced by angiosperms has
A.  long-term storage material inside providing food for the young embryo.
B.  a young unfertilized gametophyte inside waiting to be fertilized.
C.  a specialized chamber within which a pollen tube will grow to the ovule.
D.  All of the above
19) Sexual reproduction is a big advantage to promote gene diversity, however asexual
(vegetative) reproduction persists in plants.  Which is not a form of asexual reproduction?
A.  Apomixis
B.  Fragmentation
C.  Clonal growth in temperate tree forests
D.  Propagation from leaves
E.  Dioecy  
20) All pollen produced from which plant genotype can successfully fertilize the egg of a S1S4
A.  S1S4
B.  S2S4
C.  S4S2
D.  S2S3
21) The ovary of angiosperms has evolved various roles.  What is not a purpose of the ovary?
A.  To enhance seed distribution by becoming fruity so that it is eaten, and later defecated at a
distant locality.
B.  To enhance seed distribution by gaining structural characters enabling it to be easily blown to
new localities by the wind.
C.  To develop hooks that stick into the fur of passing animals for long distance dispersal
D.  To protect the young leaves from photo-damaging ultraviolet rays.  
22) What is (are) a way(s) to break seed dormancy?
A.  Cold treatment   4
B.  Acid treatment
C.  Fire treatment
D.  A and B
E.  A, B, and C.
23) Introduction of foreign DNA into a plant through biolistics  
A.  is an example of grafting.
B.  is an example of sexual reproduction.
C.  is an example of asexual reproduction.
D.  is an example of modern biotechnology.
E.  is an example of protoplast fusion.
24) Which statement is true?
A. Plants have only recently (within the past 100 years) been genetically engineered by man
through selective breeding.  
B. Genetically modified organisms can only receive and express genes from closely related
C. Transgenic plants can express foreign genes that make them resistant to predators (eg. Bt
D.  DNA can only be transformed into plants during sexual recombination.
25) The equator is warmer than the poles because:
 a. The earth revolves around the sun.
 b. The earth rotates.
 c. The tilt of the earth’s axis.
 d. Light from the sun has to travel through space longer to get to the poles than to the
 e. More light from the sun is reflected away by the atmosphere at the poles than at the
26) The least important factor in shaping the climate of a region:
 a. The amount of sunlight.
 b. Global patterns of wind movement.
 c. The dominant plant and animal life of the region.
 d. Global patterns of water movement.
 e. The amount of precipitation.
27) Humans have often moved species from their native habitats to new habitats where they
can also be successful.  Select the statement about this practice that is true:
 a. It is not a wise practice, because moving even a few individuals from a native
population causes the native population to become extinct.
 b. It is not a wise practice, because introduced species often interfere with, and cause the
extinction of, native species of the new habitat.
 c. It is a sound practice, because it introduces genetic diversity that can be shared
between species.
 d. It is a sound practice, because the best situation for the earth is to have all of the same
organisms occur all over the world.
 e. None of the above.
28) While climbing up a mountain, you would observe transitions in biological communities
that are similar to those you would encounter:   5
 a. As you travel from the tropics to the poles.
 b. In a community through different seasons.
 c. In an ecosystem as it evolves over time.
 d. As you travel across the United States from east to west.
 e. As you travel across the United States from west to east.
29) Select the correct arrangement of biomes from least to most stratified:
 a. Tropical forest, tundra, temperate forest, coniferous forest.
 b. Coniferous forest, tundra, temperate forest, tropical forest.
 c. Tundra, coniferous forest, tropical forest, temperate forest.
 d. Tundra, temperate forest, coniferous forest, tropical forest.
 e. Tundra, coniferous forest, temperate forest, tropical forest.
30) Select the biome that is not adapted to frequent fires.
 a. Desert.
 b. Savanna.
 c. Chaparral.
 d. Temperate grassland.
 e. None of the above.
31) Gymnosperms are the dominant plants in:
 a. Coniferous forests.
 b. Tundra.
 c. Temperate forests.
 d. Tropical forests.
 e. Deserts.
32) The aquatic community that would be least affected by reduction in sunlight:
 a. Coral reef.
 b. Lake.
 c. Ocean pelagic.
 d. Hydrothermal vent.
 e. Intertidal.
33) Select the incorrect match between the biome and its characteristic feature
 a. Pond: may experience great temperature fluctuations.
 b. Wetlands: covered by salt water.
 c. Intertidal: organisms are adapted to waves.
 d. Coral reefs: found only in shallow waters.
 e. Ocean pelagic: the major source of the world’s oxygen.
34) Select in incorrect match between a dispersion pattern and its feature:
 a. Random: individuals are evenly spaced.
 b. Clumped: the most common dispersion pattern in nature.
 c. Uniform: the result of antagonistic interactions among individuals.
 d. Clumped: the result of positive interactions among individuals.
 e. Clumped: the result of individuals clustering where resources are localized.
35) The most unlikely organism is one that reproduces:
 a. once, producing many small offspring, and lives a short time
 b. many times, producing few small offspring each time, and lives a short time   6
 c. many times, producing few large offspring each time, and lives a long time
 d. many times, producing many large offspring each time, and lives a long time.
 e. many times, producing many large offspring each time, and lives a short time.
36)  Not a usual feature of an r-strategist:
 a. Adapted to disturbed habitats.
 b. Small body size.
 c. Parental care.
 d. Generalists.
 e. Short-lived.
37) When species are introduced into a new area and exhibit an initial period of exponential
growth, this is because:
 a. Introduced species always survive better in a new habitat.
 b. All species show an exponential growth curve.
 c. Native species compete with the introduced species.
 d. Resources are abundant and predators are absent.
 e. The introduced species has reached carrying capacity.
38) Select that statement that is false:
 a. Large organisms usually have lower population densities than small organisms.
 b. Small populations face a greater risk of extinction than large populations.
 c. Survival in young is greater in reptiles than in amphibians.
 d. Mortality in young is less in mammals than in most invertebrates.
 e. A population in which most of the members are pre-reproductive is declining.
39) At high population densities, an increase in population size causes the following to
 a. Aggressive behavior.
 b. Emigration.
 c. Spread of infectious diseases.
 d. The age when an organism first reproduces.
 e. The strength of the immune system
40) Select the statement that is true about human population growth:
 a. We have not yet begun exponential population growth.
 b. We have reached carrying capacity and our population size is stabilizing.
 c. We have increased the carrying capacity of the places where we live.
 d. Our growth is limited by our ability to live in only a few places on earth.
 e. Our growth is limited by increasing death rates.
41) Select the statement that is false about ecological footprint:
 a. One variable used to calculate the ecological footprint is the land required for
vegetation to absorb the carbon dioxide produced by burning fossil fuels.
 b. Ecological footprint measures the amount of land and water needed by a nation to
produce all the resources it consumes and to absorb all the waste it generates.
 c. Ecological footprint can be compared to the actual ecological capacity of a nation to
determine if that nation is in ecological deficit.
 d. The United States is in ecological deficit.
 e. The world in general is not yet in ecological deficit.
42) Resource partitioning would be most likely to occur between:
 a. populations of a predator and its prey that live in the same area.
 b. populations of two species with similar needs that live in the same area.
 c. populations of a flowering plant and its specialized insect pollinator.
 d. populations of the same animal species that live in different areas.
 e. populations of two species with similar needs that live in different areas.
43) Which of the following is not an example of a plant defense against herbivory?
 a. Toxins such as nicotine.
 b. Cryptic coloration.
 c. Thorns.
 d. Sticky fluids
 e. Bark
44) Which of the following is an example of Batesian mimicry?
 a. An insect that resembles a twig.
 b. A butterfly that resembles a leaf.
 c. A non-venomous snake that looks like a venomous snake.
 d. A fawn with fur coloring that camouflages it in the forest.
 e. A snapping turtle that uses its tongue to mimic a worm, thus attracting fish.
45) The mildest infectious diseases are those caused by agents that:
 a. Can live long outside their host.
 b. Are transmitted easily by vectors.
 c. Are transmitted easily by contaminated water.
 d. Kill their host quickly.
 e. Need the host for the agent to be transmitted to a new host.
46) Select the statement that is false about the arms race (shown in a video played in class)
between the poisonous newt and the garter snake:
 a. The newt is more poisonous than it needs to be to kill most of its predators.
 b. Resistance to the newt toxins comes at a cost to the garter snake.
 c. Newts increase in toxicity as a result of their conscious effort.
 d. Resistance in snakes to the newt toxins results from evolution by natural selection.
 e. The newt toxins are harmless if touched but harmful if ingested.
47) The role humans play in food webs:
 a. Decomposers.
 b. Primary producers.
 c. Primary consumers.
 d. Secondary consumers.
 e. Both primary and secondary consumers
48) Select the statement about succession that is correct:
 a. An example of primary succession is young trees growing in the place of fallen tree.
 b. Disturbances delay the appearance of climax communities.
 c. During succession, communities become simpler.
 d. Climax communities do not change because climate does not change.
 e. Pioneer species are usually specialists.
49) The main decomposers in ecosystems:   8
 a. Animals and plants.
 b. Bacteria and fungi.
 c. Animals and fungi
 d. Bacteria and plants
 e. Plants and fungi
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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
photosynthetic productivity.
 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:
 a. Producers.
 b. Producers and decomposers.
 c. 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
 a. cycle  
 b.  rutabaga
 c.  adenylate cyclase
 d.  discs-large
 e.  turnip
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
cell nucleus
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?
 a)  Cnidaria
 b)  Cephalochordata
 c)  Annelida
 d)  Nematoda
 e)  Echinodermata
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.
 d)  eyes.
 e)  echinoderm tube-feet.
68) Which one of the following groups of mammals lays eggs?
 a)  sea cows
 b)  platypuses
 c)  sea horses
 d)  kangaroos
 e)  elephants
69) Of the following primate species or groups, which is most distantly related to humans?
 a)  Chimpanzees
 b)  Gibbons
 c)  Orangutan
 d)  Old world monkeys   11
 e)  Gorillas
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:
 a) cilia
 b) capillaries
 c) elastin
 d) a and b
 e) none of the above
73)   Muscles are joined to bones by
    a. fascia
    b. tendons.
    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
the axon.
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?  
     a.  cortisone  
     b.  testosterone  
     c.  androgen  
     d.  estrogen  
     e.  insulin  
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?  
     a.  mouse.  
     b.  spiny echidna
     c.  horse  
     d.  elephant  
     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  
     c.  trophoblast  
     d.  allantois  
     e.  chorion  
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
removed because:
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:
A.  GA
C.  Auxin
D.  Cytokinin
E.  Ethylene
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:
A.  Cytokinin
B.  Auxin
C.  Ethylene
D.  GA
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:
A.  Sucrose
B.  Starch
C.  Glucose
D.  Fructose
E.  Amylose
94) The major driving force for the upward movement of water in the xylem is
A.  guttation
B.  solute potential
C.  physical pressure from the cell wall
D.  transpiration
E.  protons
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:
A. Apoplastic
B.  cytosolic
C. Symplastic
D. transmembrane
E. vacuolar
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
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