Question 1

In order for a plant to initiate chemical responses to herbivory,

Accepted Answer

A)  the plant must be directly attacked by an herbivore. 
B)  volatile "signal" compounds must be perceived. 
C)  gene-for-gene recognition must occur. 
D)  phytoalexins must be released. 
E)  it must be past a certain developmental age. 
A)  the plant must be directly attacked by an herbivore. 
B)  volatile "signal" compounds must be perceived. 
C)  gene-for-gene recognition must occur. 
D)  phytoalexins must be released. 
E)  it must be past a certain developmental age.

Question 2

This experiment suggests that the unknown amount of gibberellin in the experimental plant (B)is approximately

Accepted Answer

A)  zero. 
B)  0.01 μg/mL. 
C)  0.1 μg/mL. 
D)  1.0 μg/mL. 
E)  equal to the amount of gibberellin in the shortest plant. 
A)  zero. 
B)  0.01 μg/mL. 
C)  0.1 μg/mL. 
D)  1.0 μg/mL. 
E)  equal to the amount of gibberellin in the shortest plant.

Question 3

We know from the experiments of the past that plants bend toward light because

Accepted Answer

A)  they need sunlight energy for photosynthesis. 
B)  the sun stimulates stem growth. 
C)  cell expansion is greater on the dark side of the stem. 
D)  auxin is inactive on the dark side of the stem. 
E)  phytochrome stimulates florigen production. 
A)  they need sunlight energy for photosynthesis. 
B)  the sun stimulates stem growth. 
C)  cell expansion is greater on the dark side of the stem. 
D)  auxin is inactive on the dark side of the stem. 
E)  phytochrome stimulates florigen production.

Question 4

Evidence for phototropism due to the asymmetric distribution of auxin moving down the stem

Accepted Answer

A)  was first demonstrated in the coleoptiles of monocots. 
B)  has been found in all monocots and most eudicots. 
C)  has been shown to involve only IAA stimulation of cell elongation on the dark side of the stem. 
D)  can be demonstrated with unilateral red light, but not blue light. 
E)  is now thought by most plant scientists not to involve the shoot tip. 
A)  was first demonstrated in the coleoptiles of monocots. 
B)  has been found in all monocots and most eudicots. 
C)  has been shown to involve only IAA stimulation of cell elongation on the dark side of the stem. 
D)  can be demonstrated with unilateral red light, but not blue light. 
E)  is now thought by most plant scientists not to involve the shoot tip.

Question 5

The detector of light during de-etiolation (greening)of a tomato plant is (are)

Accepted Answer

A)  carotenoids. 
B)  xanthophylls. 
C)  phytochrome. 
D)  chlorophyll. 
E)  auxin. 
A)  carotenoids. 
B)  xanthophylls. 
C)  phytochrome. 
D)  chlorophyll. 
E)  auxin.

Question 6

How may a plant respond to severe heat stress?

Accepted Answer

A)  by reorienting leaves to increase evaporative cooling 
B)  by creating air tubes for ventilation 
C)  by initiating a systemic acquired resistance response 
D)  by increasing the proportion of unsaturated fatty acids in cell membranes, reducing their fluidity 
E)  by producing heat-shock proteins, which may protect the plant's proteins from denaturing 
A)  by reorienting leaves to increase evaporative cooling 
B)  by creating air tubes for ventilation 
C)  by initiating a systemic acquired resistance response 
D)  by increasing the proportion of unsaturated fatty acids in cell membranes, reducing their fluidity 
E)  by producing heat-shock proteins, which may protect the plant's proteins from denaturing

Question 7

The houseplants in a windowless room with only fluorescent lights begin to grow tall and leggy. Which of the following treatments would promote more normal growth?

Accepted Answer

A)  Leave the lights on at night as well as during the day. 
B)  Add additional fluorescent tubes to increase the light output. 
C)  Add some incandescent bulbs to increase the amount of red light. 
D)  Set a timer to turn on the lights for 5 minutes during the night. 
E)  Turn off the lights for 5 minutes during the day. 
A)  Leave the lights on at night as well as during the day. 
B)  Add additional fluorescent tubes to increase the light output. 
C)  Add some incandescent bulbs to increase the amount of red light. 
D)  Set a timer to turn on the lights for 5 minutes during the night. 
E)  Turn off the lights for 5 minutes during the day.

Question 8

According to modern ideas about phototropism in plants,

Accepted Answer

A)  light causes auxin to accumulate on the shaded side of a plant stem. 
B)  auxin indirectly inhibits elongation of plant stem cells. 
C)  auxin is produced by the apical meristem of the coleoptile and moves downward. 
D)  all hormones move downward via the xylem. 
E)  cytokinins are more directly involved than auxins. 
A)  light causes auxin to accumulate on the shaded side of a plant stem. 
B)  auxin indirectly inhibits elongation of plant stem cells. 
C)  auxin is produced by the apical meristem of the coleoptile and moves downward. 
D)  all hormones move downward via the xylem. 
E)  cytokinins are more directly involved than auxins.

Exam 39: Plant Responses to Internal and External Signals

In order for a plant to initiate chemical responses to herbivory,

This experiment suggests that the unknown amount of gibberellin in the experimental plant (B)is approximately

We know from the experiments of the past that plants bend toward light because

Evidence for phototropism due to the asymmetric distribution of auxin moving down the stem

The detector of light during de-etiolation (greening)of a tomato plant is (are)

How may a plant respond to severe heat stress?

The houseplants in a windowless room with only fluorescent lights begin to grow tall and leggy. Which of the following treatments would promote more normal growth?

According to modern ideas about phototropism in plants,

Introduction: Themes in the Study of Life

The Chemical Context of Life

Water and Life

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 and Fermentation

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

Regulation 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 Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure, Growth, and Development

Resource Acquisition and 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 and Restoration Ecology

Conservation Biology and Global Change

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