Question 1

Plants that have their flowering inhibited by being exposed to bright lights at night are

Accepted Answer

A) day-neutral plants. 
B) short-night plants. 
C) devoid of phytochrome. 
D) short-day plants. 
E) long-day plants. 
A) day-neutral plants. 
B) short-night plants. 
C) devoid of phytochrome. 
D) short-day plants. 
E) long-day plants. D

Question 2

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. C

Question 3

Which of the following plant hormones are most likely to act synergistically if expressed or applied to a drought-stricken plant?

Accepted Answer

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

Question 4

A plant seedling bends toward sunlight because

Accepted Answer

A) auxin migrates to the lower part of the stem due to gravity. 
B) there is more auxin on the light side of the stem. 
C) auxin is destroyed more quickly on the dark side of the stem. 
D) auxin is found in greatest abundance on the dark side of the stem. 
E) gibberellins produced at the stem tip cause phototropism. 
A) auxin migrates to the lower part of the stem due to gravity. 
B) there is more auxin on the light side of the stem. 
C) auxin is destroyed more quickly on the dark side of the stem. 
D) auxin is found in greatest abundance on the dark side of the stem. 
E) gibberellins produced at the stem tip cause phototropism.

Question 5

If a short-day plant has a critical night length of 15 hours,then which of the following 24-hour cycles will prevent flowering?

Accepted Answer

A) 8 hours light/16 hours dark 
B) 4 hours light/20 hours dark 
C) 6 hours light/2 hours dark/light flash/16 hours dark 
D) 8 hours light/8 hours dark/light flash/8 hours dark 
E) 2 hours light/20 hours dark/2 hours light 
A) 8 hours light/16 hours dark 
B) 4 hours light/20 hours dark 
C) 6 hours light/2 hours dark/light flash/16 hours dark 
D) 8 hours light/8 hours dark/light flash/8 hours dark 
E) 2 hours light/20 hours dark/2 hours light

Question 6

You are out working in your garden,and you notice that one of your favorite flowering plants has black,dead spots on the leaves.You immediately suspect that the plant has been invaded by a pathogen and has initiated a(n)

Accepted Answer

A) avirulence response. 
B) hypersensitive response. 
C) resistance response. 
D) virulence response. 
A) avirulence response. 
B) hypersensitive response. 
C) resistance response. 
D) virulence response.

Question 7

What is the probable role of salicylic acid in the defence responses of plants?

Accepted Answer

A) to destroy pathogens directly 
B) to activate systemic acquired resistance of plants 
C) to close stomata, thus preventing the entry of pathogens 
D) to activate heat-shock proteins 
E) to sacrifice infected tissues by hydrolyzing cells 
A) to destroy pathogens directly 
B) to activate systemic acquired resistance of plants 
C) to close stomata, thus preventing the entry of pathogens 
D) to activate heat-shock proteins 
E) to sacrifice infected tissues by hydrolyzing cells

Question 8

Why are lateral buds often inhibited from sprouting even though a stem may be actively elongating?

Accepted Answer

A) The cells of lateral buds are more sensitive to auxin than stem cells. 
B) Lateral buds are high in abscisic acid that prevents elongation. 
C) Lateral buds are low in gibberellins. 
D) Stem cells lack receptors for auxin. 
E) Stem cells can overcome auxin inhibition with high levels of gibberellins. 
A) The cells of lateral buds are more sensitive to auxin than stem cells. 
B) Lateral buds are high in abscisic acid that prevents elongation. 
C) Lateral buds are low in gibberellins. 
D) Stem cells lack receptors for auxin. 
E) Stem cells can overcome auxin inhibition with high levels of gibberellins.

Question 9

A certain bacterium infects a plant's upper leaves.A few days later,bacteria of the same species attempt to infect the same plant's roots but are unsuccessful.What process is responsible for the plant's ability to prevent this infection?

Accepted Answer

A) antivirulence response 
B) pathogenesis resistance 
C) systemic acquired resistance 
D) sequential immunity 
A) antivirulence response 
B) pathogenesis resistance 
C) systemic acquired resistance 
D) sequential immunity

Question 10

While ________ inhibit(s)early germination,________ regulate(s)cell division in shoots and roots.

Accepted Answer

A) gibberellins; auxin 
B) ethylene; cytokinins 
C) auxin; ethylene 
D) ABA; cytokinins 
E) strigolactones; gibberellins 
A) gibberellins; auxin 
B) ethylene; cytokinins 
C) auxin; ethylene 
D) ABA; cytokinins 
E) strigolactones; gibberellins

Question 11

What do the results of research on gravitropic responses of roots and stems show?

Accepted Answer

A) Different tissues have the same response to auxin. 
B) The effect of a plant hormone can depend on the tissue. 
C) Some responses of plants require no hormones at all. 
D) Light is required for the gravitropic response. 
E) Cytokinin can only function in the presence of auxin. 
A) Different tissues have the same response to auxin. 
B) The effect of a plant hormone can depend on the tissue. 
C) Some responses of plants require no hormones at all. 
D) Light is required for the gravitropic response. 
E) Cytokinin can only function in the presence of auxin.

Question 12

________ prevents seeds from germinating until conditions are favorable for the growth of the plant.

Accepted Answer

A) Ethylene 
B) Zeaxanthin 
C) Gibberellin 
D) Abscisic acid 
A) Ethylene 
B) Zeaxanthin 
C) Gibberellin 
D) Abscisic acid

Question 13

Most scientists agree that global warming is under way; thus,it is important to know how plants respond to heat stress.Which of the following would be a useful line of inquiry to try and improve plant response and survival to heat stress?

Accepted Answer

A) the production of heat-stable carbohydrates 
B) increased production of heat-shock proteins 
C) the opening of stomata to increase evaporational heat loss 
D) protoplast fusion experiments with xerophytic plants 
E) all of the above 
A) the production of heat-stable carbohydrates 
B) increased production of heat-shock proteins 
C) the opening of stomata to increase evaporational heat loss 
D) protoplast fusion experiments with xerophytic plants 
E) all of the above

Question 14

Which of the following would be the most effective way to prevent herbivory in a non-woody plant?

Accepted Answer

A) production of the amino acid analogue canavanine 
B) release of insect pheromones 
C) production of foul-tasting compounds 
D) thickened cuticle 
E) enhanced levels of salicylic acid 
A) production of the amino acid analogue canavanine 
B) release of insect pheromones 
C) production of foul-tasting compounds 
D) thickened cuticle 
E) enhanced levels of salicylic acid

Question 15

Oat seedlings are sometimes used to study auxins because

Accepted Answer

A) they are a readily accessible monocot, and auxins affect only monocots. 
B) they have a stiff coleoptile. 
C) they green rapidly in the light. 
D) their coleoptile exhibits a strong positive phototropism. 
E) monocots inactivate synthetic auxins. 
A) they are a readily accessible monocot, and auxins affect only monocots. 
B) they have a stiff coleoptile. 
C) they green rapidly in the light. 
D) their coleoptile exhibits a strong positive phototropism. 
E) monocots inactivate synthetic auxins.

Question 16

The aleurone layer is stimulated to release ________ and ________ as a result of giberrellin release from the embryo.

Accepted Answer

A) proteins; amino acids 
B) carbohydrates; sugars 
C) auxins; cytokinins 
D) amylase; protease 
E) RNAase; DNAase 
A) proteins; amino acids 
B) carbohydrates; sugars 
C) auxins; cytokinins 
D) amylase; protease 
E) RNAase; DNAase

Question 17

We tend to think of plants as immobile when,in fact,they can move in many ways.Which of the following is a legitimate way in which plants move?

Accepted Answer

A) stretching or shrinking movements up or down in response to light 
B) folding and unfolding of leaves using muscle-like tissues 
C) growth movements toward or away from light 
D) cessation of plant growth in response to wind or touch 
E) rapid responses using action potentials from nervous tissue cells similar to those found in the nervous tissue of animals 
A) stretching or shrinking movements up or down in response to light 
B) folding and unfolding of leaves using muscle-like tissues 
C) growth movements toward or away from light 
D) cessation of plant growth in response to wind or touch 
E) rapid responses using action potentials from nervous tissue cells similar to those found in the nervous tissue of animals

Question 18

Which of the following is a likely response of plants to cold stress?

Accepted Answer

A) the production of a specific solute "plant coagulant" that reduces water loss 
B) reducing the size of ice crystals 
C) conversion of the fluid mosaic cell membrane to a solid mosaic one 
D) an increase in sterol concentration of membrane lipids so that the membranes remain flexible 
E) increasing the proportion of unsaturated fatty acids in the membranes 
A) the production of a specific solute "plant coagulant" that reduces water loss 
B) reducing the size of ice crystals 
C) conversion of the fluid mosaic cell membrane to a solid mosaic one 
D) an increase in sterol concentration of membrane lipids so that the membranes remain flexible 
E) increasing the proportion of unsaturated fatty acids in the membranes

Question 19

If you were shipping green bananas to a supermarket thousands of miles away,which of the following chemicals would you want to eliminate from the plants' environment?

Accepted Answer

A) CO₂ 
B) cytokinins 
C) ethylene 
D) auxin 
E) gibberellic acids 
A) CO₂ 
B) cytokinins 
C) ethylene 
D) auxin 
E) gibberellic acids

Question 20

Auxin enhances cell elongation in all of the these ways except

Accepted Answer

A) increased uptake of solutes. 
B) gene activation. 
C) acid-induced denaturation of cell wall proteins. 
D) increased activity of plasma membrane proton pumps. 
E) cell wall loosening. 
A) increased uptake of solutes. 
B) gene activation. 
C) acid-induced denaturation of cell wall proteins. 
D) increased activity of plasma membrane proton pumps. 
E) cell wall loosening.

Exam 39: Plant Responses to Internal and External Signals

Plants that have their flowering inhibited by being exposed to bright lights at night are

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

Which of the following plant hormones are most likely to act synergistically if expressed or applied to a drought-stricken plant?

A plant seedling bends toward sunlight because

If a short-day plant has a critical night length of 15 hours,then which of the following 24-hour cycles will prevent flowering?

You are out working in your garden,and you notice that one of your favorite flowering plants has black,dead spots on the leaves.You immediately suspect that the plant has been invaded by a pathogen and has initiated a(n)

What is the probable role of salicylic acid in the defence responses of plants?

Why are lateral buds often inhibited from sprouting even though a stem may be actively elongating?

A certain bacterium infects a plant's upper leaves.A few days later,bacteria of the same species attempt to infect the same plant's roots but are unsuccessful.What process is responsible for the plant's ability to prevent this infection?

While ________ inhibit(s)early germination,________ regulate(s)cell division in shoots and roots.

What do the results of research on gravitropic responses of roots and stems show?

________ prevents seeds from germinating until conditions are favorable for the growth of the plant.

Most scientists agree that global warming is under way; thus,it is important to know how plants respond to heat stress.Which of the following would be a useful line of inquiry to try and improve plant response and survival to heat stress?

Which of the following would be the most effective way to prevent herbivory in a non-woody plant?

Oat seedlings are sometimes used to study auxins because

The aleurone layer is stimulated to release ________ and ________ as a result of giberrellin release from the embryo.

We tend to think of plants as immobile when,in fact,they can move in many ways.Which of the following is a legitimate way in which plants move?

Which of the following is a likely response of plants to cold stress?

If you were shipping green bananas to a supermarket thousands of miles away,which of the following chemicals would you want to eliminate from the plants' environment?

Auxin enhances cell elongation in all of the these ways except

Introduction: Evolution and Themes of Biology

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

DNA Tools and 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 Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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While inhibit(s)early germination, regulate(s)cell division in shoots and roots.

The aleurone layer is stimulated to release and as a result of giberrellin release from the embryo.