Question 1

Which of the following are defenses that some plants use against herbivory?

Accepted Answer

A) production of the unusual amino acid canavanine 
B) release of volatile compounds that attract parasitoid wasps 
C) association of plant tissues with mycorrhizae 
D) A and B only 
E) A, B, and C 
A) production of the unusual amino acid canavanine 
B) release of volatile compounds that attract parasitoid wasps 
C) association of plant tissues with mycorrhizae 
D) A and B only 
E) A, B, and C D

Question 2

Auxin enhances cell elongation in all of these ways except

Accepted Answer

A) increased uptake of solutes. 
B) gene activation. 
C) acidification of the cell wall, causing denaturation of growth-inhibiting cell wall proteins. 
D) increased activity of plasma membrane proton pumps. 
E) cell wall loosening. 
A) increased uptake of solutes. 
B) gene activation. 
C) acidification of the cell wall, causing denaturation of growth-inhibiting cell wall proteins. 
D) increased activity of plasma membrane proton pumps. 
E) cell wall loosening. C

Question 3

A pathogenic fungus invades a plant. What does the infected plant produce in response to the attack?

Accepted Answer

A) antisense RNA 
B) phytoalexins 
C) phytochrome 
D) statoliths 
E) thickened cellulose microfibrils in the cell wall 
A) antisense RNA 
B) phytoalexins 
C) phytochrome 
D) statoliths 
E) thickened cellulose microfibrils in the cell wall B

Question 4

1.92 The detector of light during de-etiolation (greening)of the tomato plant are carotenoid pigments

Accepted Answer

A) True 
 B)False

Question 5

Which of the following does not reduce the level of the Pfr form of phytochrome?

Accepted Answer

A) exposure to far-red light 
B) exposure to red light 
C) long dark period 
D) destruction of phytochrome 
E) synthesis of phosphorylating enzymes 
A) exposure to far-red light 
B) exposure to red light 
C) long dark period 
D) destruction of phytochrome 
E) synthesis of phosphorylating enzymes

Question 6

If you wanted to genetically engineer a plant to be more resistant to drought, increasing amounts of which of the following hormones might be a good first attempt?

Accepted Answer

A) abscisic acid 
B) brassinosteroids 
C) gibberellins 
D) cytokinins 
E) auxin 
A) abscisic acid 
B) brassinosteroids 
C) gibberellins 
D) cytokinins 
E) auxin

Question 7

Most plants close their stomata at night. What color of light would be most effective in promoting stomatal opening in the middle of the night?

Accepted Answer

A) red 
B) far-red 
C) blue 
D) red followed by far-red 
E) far-red followed by blue 
A) red 
B) far-red 
C) blue 
D) red followed by far-red 
E) far-red followed by blue

Question 8

Biological clocks cause organisms to perform daily activities on a regular basis. Which of the following is a False statement about this kind of "circadian rhythm"?

Accepted Answer

A) It may have the same signal transduction pathway in all organisms. 
B) It must be reset on a daily basis. 
C) It may help to cause photoperiodic responses. 
D) Once set, it is independent of external signals. 
E) The exact mechanism of biological clocks remains unknown. 
A) It may have the same signal transduction pathway in all organisms. 
B) It must be reset on a daily basis. 
C) It may help to cause photoperiodic responses. 
D) Once set, it is independent of external signals. 
E) The exact mechanism of biological clocks remains unknown.

Question 9

In legumes, it has been shown that "sleep" movements are correlated with

Accepted Answer

A) positive thigmotropisms. 
B) rhythmic opening and closing of K+ channels in motor cell membranes. 
C) senescence (the aging process in plants). 
D) flowering and fruit development. 
E) ABA-stimulated closing of guard cells caused by loss of K+. 
A) positive thigmotropisms. 
B) rhythmic opening and closing of K+ channels in motor cell membranes. 
C) senescence (the aging process in plants). 
D) flowering and fruit development. 
E) ABA-stimulated closing of guard cells caused by loss of K+.

Question 10

Which plant hormone(s)is (are)most closely associated with cell division?

Accepted Answer

A) ethylene 
B) cytokinin 
C) abscisic acid 
D) phytochrome 
E) brassinosteroids 
A) ethylene 
B) cytokinin 
C) abscisic acid 
D) phytochrome 
E) brassinosteroids

Question 11

Vines in tropical rain forests must grow toward large trees before being able to grow toward the sun. To reach a large tree, the most useful kind of growth movement for a tropical vine presumably would be the opposite of

Accepted Answer

A) positive thigmotropism. 
B) positive phototropism. 
C) positive gravitropism. 
D) sleep movements. 
E) circadian rhythms. 
A) positive thigmotropism. 
B) positive phototropism. 
C) positive gravitropism. 
D) sleep movements. 
E) circadian rhythms.

Question 12

The initial response of the root cells of a tomato plant watered with seawater would be to

Accepted Answer

A) rapidly produce organic solutes in the cytoplasm. 
B) rapidly expand until the cells burst. 
C) begin to plasmolyze as water is lost. 
D) actively transport water from the cytoplasm into the vacuole. 
E) actively absorb salts from the seawater. 
A) rapidly produce organic solutes in the cytoplasm. 
B) rapidly expand until the cells burst. 
C) begin to plasmolyze as water is lost. 
D) actively transport water from the cytoplasm into the vacuole. 
E) actively absorb salts from the seawater.

Question 13

A plant will recognize a pathogenic invader

Accepted Answer

A) if it has many specific plant disease resistance (R)genes. 
B) when the pathogen has an R gene complementary to the plant's antivirulence (Avr)gene. 
C) only if the pathogen and the plant have the same R genes. 
D) if it has the specific R gene that corresponds to the pathogen molecule encoded by an Avr gene. 
E) when the pathogen secretes Avr protein. 
A) if it has many specific plant disease resistance (R)genes. 
B) when the pathogen has an R gene complementary to the plant's antivirulence (Avr)gene. 
C) only if the pathogen and the plant have the same R genes. 
D) if it has the specific R gene that corresponds to the pathogen molecule encoded by an Avr gene. 
E) when the pathogen secretes Avr protein.

Question 14

A botanist discovers a plant that lacks the ability to form starch grains in root cells, yet the roots still grow downward. This evidence refutes the long-standing hypothesis that

Accepted Answer

A) falling statoliths trigger gravitropism. 
B) starch accumulation triggers the negative phototropic response of roots. 
C) starch grains block the acid growth response in roots. 
D) starch is converted to auxin, which causes the downward bending in roots. 
E) starch and downward movement are necessary for thigmotropism. 
A) falling statoliths trigger gravitropism. 
B) starch accumulation triggers the negative phototropic response of roots. 
C) starch grains block the acid growth response in roots. 
D) starch is converted to auxin, which causes the downward bending in roots. 
E) starch and downward movement are necessary for thigmotropism.

Question 15

If the range of a species of plants expands to a higher latitude, which of the following processes is the most likely to be modified by natural selection?

Accepted Answer

A) circadian rhythm 
B) photoperiodic response 
C) phototropic response 
D) biological clock 
E) thigmomorphogenesis 
A) circadian rhythm 
B) photoperiodic response 
C) phototropic response 
D) biological clock 
E) thigmomorphogenesis

Question 16

The biological clock controlling circadian rhythms must ultimately

Accepted Answer

A) depend on environmental cues. 
B) affect gene transcription. 
C) stabilize on a 24-hour cycle. 
D) speed up or slow down with increasing or decreasing temperature. 
E) do all of the above. 
A) depend on environmental cues. 
B) affect gene transcription. 
C) stabilize on a 24-hour cycle. 
D) speed up or slow down with increasing or decreasing temperature. 
E) do all of the above.

Question 17

Experiments on the positive phototropic response of plants indicate that light destroys auxin.

Accepted Answer

A) True 
 B)False

Question 18

According to the acid growth hypothesis, auxin works by

Accepted Answer

A) dissolving sieve plates, permitting more rapid transport of nutrients. 
B) dissolving the cell membranes temporarily, permitting cells that were on the verge of dividing to divide more rapidly. 
C) changing the pH within the cell, which would permit the electron transport chain to operate more efficiently. 
D) increasing wall plasticity and allowing the affected cell walls to elongate. 
E) greatly increasing the rate of deposition of cell wall material. 
A) dissolving sieve plates, permitting more rapid transport of nutrients. 
B) dissolving the cell membranes temporarily, permitting cells that were on the verge of dividing to divide more rapidly. 
C) changing the pH within the cell, which would permit the electron transport chain to operate more efficiently. 
D) increasing wall plasticity and allowing the affected cell walls to elongate. 
E) greatly increasing the rate of deposition of cell wall material.

Question 19

Plants growing in a partially dark environment will grow toward light in a response called phototropism. Choose the incorrect statement regarding phototropism.

Accepted Answer

A) It is caused by a chemical signal. 
B) One chemical involved is auxin. 
C) Auxin causes a growth increase on one side of the stem. 
D) Auxin causes a decrease in growth on the side of the stem exposed to light. 
E) Removing the apical meristem prevents phototropism. 
A) It is caused by a chemical signal. 
B) One chemical involved is auxin. 
C) Auxin causes a growth increase on one side of the stem. 
D) Auxin causes a decrease in growth on the side of the stem exposed to light. 
E) Removing the apical meristem prevents phototropism.

Question 20

Roots exhibit negative geotropism whereas stems exhibit positive geotropism.

Accepted Answer

A) True 
 B)False

Exam 39: Plant Responses to Internal and External Signals

Which of the following are defenses that some plants use against herbivory?

Auxin enhances cell elongation in all of these ways except

A pathogenic fungus invades a plant. What does the infected plant produce in response to the attack?

1.92 The detector of light during de-etiolation (greening)of the tomato plant are carotenoid pigments

Which of the following does not reduce the level of the Pfr form of phytochrome?

If you wanted to genetically engineer a plant to be more resistant to drought, increasing amounts of which of the following hormones might be a good first attempt?

Most plants close their stomata at night. What color of light would be most effective in promoting stomatal opening in the middle of the night?

Biological clocks cause organisms to perform daily activities on a regular basis. Which of the following is a False statement about this kind of "circadian rhythm"?

In legumes, it has been shown that "sleep" movements are correlated with

Which plant hormone(s)is (are)most closely associated with cell division?

Vines in tropical rain forests must grow toward large trees before being able to grow toward the sun. To reach a large tree, the most useful kind of growth movement for a tropical vine presumably would be the opposite of

The initial response of the root cells of a tomato plant watered with seawater would be to

A plant will recognize a pathogenic invader

A botanist discovers a plant that lacks the ability to form starch grains in root cells, yet the roots still grow downward. This evidence refutes the long-standing hypothesis that

If the range of a species of plants expands to a higher latitude, which of the following processes is the most likely to be modified by natural selection?

The biological clock controlling circadian rhythms must ultimately

Experiments on the positive phototropic response of plants indicate that light destroys auxin.

According to the acid growth hypothesis, auxin works by

Plants growing in a partially dark environment will grow toward light in a response called phototropism. Choose the incorrect statement regarding phototropism.

Roots exhibit negative geotropism whereas stems exhibit positive geotropism.

Introduction: Themes in the Study of Life

The Chemical Context of Life

Water and the Fitness of the Environment

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration: Harvesting Chemical Energy

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Control of Gene Expression

Viruses

Biotechnology

Genomes and Their Evolution

Descent With Modification: a Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity Ii: the Evolution of Seed Plants

Fungi

An Introduction to Animal Diversity

Invertebrates

Vertebrates

Plant Structure, Growth, and Development

Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems

Conservation Biology and Restoration Ecology

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