Question 1

The addition of a phosphate group to a protein is called _ _, and it usually results in .

Accepted Answer

A)  phosphorylation; protein activation or inactivation 
B)  dephosphorylation; mutation 
C)  signal transduction; changes in gene transcription 
D)  oxidation; changes in growth patterns 
A)  phosphorylation; protein activation or inactivation 
B)  dephosphorylation; mutation 
C)  signal transduction; changes in gene transcription 
D)  oxidation; changes in growth patterns A

Question 2

What do phototropin and ABA have in common?

Accepted Answer

A)  They regulate opening and closing of water pores in the plasma membrane. 
B)  They are localized in the plasma membrane. 
C)  They regulate activity of H+- ATPases. 
D)  They are blue light photoreceptors. 
E)  They induce stomata closing. 
A)  They regulate opening and closing of water pores in the plasma membrane. 
B)  They are localized in the plasma membrane. 
C)  They regulate activity of H+- ATPases. 
D)  They are blue light photoreceptors. 
E)  They induce stomata closing. C

Question 3

Which of the following is the strongest evidence that cytokinins regulate cell divisions?

Accepted Answer

A)  induction of root growths in tissues exposed to cytokinin 
B)  induction of shoot growths in tissues exposed to cytokinin 
C)  decrease of cyclin gene expression in tissues exposed to cytokinin 
D)  ability of cytokinin to interact with auxin at the molecular level and change auxin biosynthesis and transport 
E)  increase of cyclin gene expression in tissues exposed to cytokinin 
A)  induction of root growths in tissues exposed to cytokinin 
B)  induction of shoot growths in tissues exposed to cytokinin 
C)  decrease of cyclin gene expression in tissues exposed to cytokinin 
D)  ability of cytokinin to interact with auxin at the molecular level and change auxin biosynthesis and transport 
E)  increase of cyclin gene expression in tissues exposed to cytokinin E

Question 4

You have discovered a previously unidentified plant, and you cultivate it in your lab. You notice that its flowers close when people are talking, yet are open when the lab is relatively quiet. You suspect that this plant may have the ability to hear! Based on what you know about plant sensation, which of the following hypotheses is the most reasonable to explain this phenomenon?

Accepted Answer

A)  There is a cell- surface receptor on root cells that becomes phosphorylated when the soil vibrates in response to sound waves. 
B)  There is a cell- surface protein on the epidermal cells that becomes phosphorylated in response to vibration by sound waves. 
C)  There are tiny hairs on epidermal cells that bend in response to the vibration of sound waves, triggering an action potential in epidermal cells. 
D)  All of the above answers are correct. 
A)  There is a cell- surface receptor on root cells that becomes phosphorylated when the soil vibrates in response to sound waves. 
B)  There is a cell- surface protein on the epidermal cells that becomes phosphorylated in response to vibration by sound waves. 
C)  There are tiny hairs on epidermal cells that bend in response to the vibration of sound waves, triggering an action potential in epidermal cells. 
D)  All of the above answers are correct.

Question 5

Upon exposure to blue light, plants not only begin to grow toward the light, but move their chloroplasts to the sunny side of each cell. Why would it be advantageous to move chloroplasts within cells?

Accepted Answer

A)  moving chloroplasts is not advantageous because it requires an input of energy 
B)  to maximize light absorption by the chloroplasts for photosynthesis 
C)  to maximize heat absorption by the chloroplasts for cellular respiration 
D)  to add weight to the sunny side of the plant so the plant will bend 
E)  to reduce stomatal opening on the sunny side of the plants 
A)  moving chloroplasts is not advantageous because it requires an input of energy 
B)  to maximize light absorption by the chloroplasts for photosynthesis 
C)  to maximize heat absorption by the chloroplasts for cellular respiration 
D)  to add weight to the sunny side of the plant so the plant will bend 
E)  to reduce stomatal opening on the sunny side of the plants

Question 6

Why does auxin move through the plant slower than sucrose does?

Accepted Answer

A)  Auxin transport through phloem is slower than sucrose transport through parenchyma cells. 
B)  Both auxin and sucrose are transported through phloem and parenchyma cells, but auxin is a bigger molecule and moves slower by diffusion. 
C)  Auxin transport is active requires energy) while sucrose transport is passive. 
D)  Auxin is transported by diffusion while cotransporters are involved in sucrose transport. 
E)  Auxin transport through parenchyma cells is slower than sucrose transport through phloem. 
A)  Auxin transport through phloem is slower than sucrose transport through parenchyma cells. 
B)  Both auxin and sucrose are transported through phloem and parenchyma cells, but auxin is a bigger molecule and moves slower by diffusion. 
C)  Auxin transport is active requires energy) while sucrose transport is passive. 
D)  Auxin is transported by diffusion while cotransporters are involved in sucrose transport. 
E)  Auxin transport through parenchyma cells is slower than sucrose transport through phloem.

Question 7

$\begin{array}{c}
\begin{array}{|l|}
\hline\
\text {Plant}\
 \hline \text {A}\
 \hline \
\
\text {B}\
 \hline \
\
\text {C}\
 \hline
\end{array}
\begin{array}{lll}
 \hline \
 \text {Growth Conditions}\
 \hline \text {14 hours of darkness}\
 \hline \text {14 hours of darkness,}\  \text {interrupted by 10 minutes of }\
 \text {light during the fifth hour }\
 \hline \text {14 hours of light, interrupted }\
 \text {by 10 minutes of darkness}\
 \text { during the fifth hour}\
 \hline 
\end{array}
\begin{array}{|l|}
 \hline \text {Result Flowers}\
 \text {or no flowers)}\
  \hline \text {No flowers}\
 \hline\
\
 \text {No flowers}\
 \hline \
\
\text {Flowers}\
 \hline 
\end{array}

\end{array}$
 Table 37.1
-Refer to the table above. Why did plant B fail to flower?

Accepted Answer

A)  Flowering was inhibited by the excess of far- red light. 
B)  It sensed a nine- hour day. 
C)  It sensed a nine- hour night. 
D)  There was not enough blue- light exposure to trigger flowering. 
A)  Flowering was inhibited by the excess of far- red light. 
B)  It sensed a nine- hour day. 
C)  It sensed a nine- hour night. 
D)  There was not enough blue- light exposure to trigger flowering.

Question 8

Use the following information when answering the corresponding questions).
Some plants continually produce secondary defense compounds. Other plants are induced to form secondary defense compou when they are injured. Corn seedling leaves that are chewed on by the caterpillars of a type of cutworm moth emit immediate chemicals LOX products), and, after six hours, large amounts of terpenoid compounds are released into the air. The terpenoid are released not only from the leaf being chewed, but from all leaves of the plant. The terpenoid compounds attract a parasitoid wasp female that lays her eggs on the caterpillar. When the wasp larvae hatch, they eat and kill the moth caterpillar. T.C.J. Turlings, J. H. Loughrin, P. J. McCall, U. S. R. Rose, W. J. Lewis, and J. H. Tumlinson. 1995. How
caterpillar- damaged plants protect themselves by attracting parasitic wasps. Proceedings of the National Academy of Science
92:4169- 74.)
-How could you test the hypothesis that compounds from the caterpillar alone do not attract parasitoid wasps?

Accepted Answer

A)  Have caterpillars feed on different kinds of plants in the presence of the wasps. 
B)  Place intact corn seedlings in an enclosure with the wasps. 
C)  Place non- feeding caterpillars in an enclosure with the wasps. 
A)  Have caterpillars feed on different kinds of plants in the presence of the wasps. 
B)  Place intact corn seedlings in an enclosure with the wasps. 
C)  Place non- feeding caterpillars in an enclosure with the wasps.

Question 9

A caterpillar eats a leaf of a plant. The next day it crawls to a nearby leaf to eat. But after eating the second leaf, the caterpillar gets very sick and falls off the plant. Which of the following molecules were involved in the plant's ability to defend itself against the second attack?

Accepted Answer

A)  proteinase inhibitors 
B)  systemin 
C)  jasmonic acid 
D)  all of the above 
E)  A and C only 
A)  proteinase inhibitors 
B)  systemin 
C)  jasmonic acid 
D)  all of the above 
E)  A and C only

Question 10

Which of the following events would be initially triggered by a signal transduction cascade?

Accepted Answer

A)  activation of translation 
B)  change in the receptor protein's shape 
C)  activation of transcription 
D)  change in ion flow through a membrane channel 
A)  activation of translation 
B)  change in the receptor protein's shape 
C)  activation of transcription 
D)  change in ion flow through a membrane channel

Question 11

You discover a chemical that inhibits the conversion of starch to sugar and inhibits the breakdown of chlorophyll and cellulose in fruit. Who might be interested in buying this chemical?

Accepted Answer

A)  grocers, to spray on fruit to enhance ripening in the store 
B)  consumers, to spray on fruit before eating to enhance taste 
C)  farmers, to spray on fruit after picking to stall ripening 
A)  grocers, to spray on fruit to enhance ripening in the store 
B)  consumers, to spray on fruit before eating to enhance taste 
C)  farmers, to spray on fruit after picking to stall ripening

Question 12

Use the following information when answering the corresponding questions).
The shade avoidance response is a plant's way of changing its growth pattern when it is being shaded by another plant. Upon to shade, many plants will grow taller, flatten their leaf angle, and extend their leaves further from their stems in order to reac sunlight. Research performed by Pierik et al. Interactions between ethylene and gibberellins in phytochrome- mediated shade avoidance responses in tobacco. 2004. Plant Physiology 136:2928- 36; online at "http://www.plantphysiol.org/cgi/content/full/136/2/2928)" http://www.plantphysiol.org/cgi/content/full/136/2/2928) examined the role of ethylene and gibberellins on the shade avoidance response in tobacco plants. The shade avoidance response is known to involve phytochromes.
-Ethylene's role in the shade avoidance response in tobacco plants is related to its role in fruit ripening, leaf abscission, and senescence.

Accepted Answer

A) True 
 B)False

Question 13

You have a bush in your yard that is the height that you want it, but not as bushy as you want it to be. How can you prune it to trigger it to get bushier?

Accepted Answer

A)  Cut off the tips of the main shoots. 
B)  Cut off the leaves at the ends of several branches. 
C)  Cut some of the higher branches off at the stem. 
D)  Cut off the leaves at the base of most of the branches. 
E)  Cut off lower branches. 
A)  Cut off the tips of the main shoots. 
B)  Cut off the leaves at the ends of several branches. 
C)  Cut some of the higher branches off at the stem. 
D)  Cut off the leaves at the base of most of the branches. 
E)  Cut off lower branches.

Question 14

If you wanted to genetically engineer a plant to be more resistant to attack by pathogenic bacteria and viruses, which of the following hormones would you manipulate?

Accepted Answer

A)  salicylic acid 
B)  auxin 
C)  abscisic acid 
D)  gibberellins 
E)  ethylene 
A)  salicylic acid 
B)  auxin 
C)  abscisic acid 
D)  gibberellins 
E)  ethylene

Question 15

You buy some fresh fruit at the grocery store. When you get home, you are in a hurry, and you put the fresh fruit in the crisper with some overripe fruit. At the end of the week you are disappointed to find that your new fruit has already become overripe. What happened?

Accepted Answer

A)  The overripe fruit released ethylene that increased the rate of ripening in the fresh fruit. 
B)  The refrigerator was probably set too high. As a result, the production of auxin was induced in overripe fruit and caused production of ethylene in the fresh fruit. 
C)  The fresh fruit was damaged, producing ethylene that sped up the ripening process. 
D)  The fresh fruit was not washed before refrigerating, so ethylene was still present on the surface of the fruit, causing the fresh fruit to overripe. 
A)  The overripe fruit released ethylene that increased the rate of ripening in the fresh fruit. 
B)  The refrigerator was probably set too high. As a result, the production of auxin was induced in overripe fruit and caused production of ethylene in the fresh fruit. 
C)  The fresh fruit was damaged, producing ethylene that sped up the ripening process. 
D)  The fresh fruit was not washed before refrigerating, so ethylene was still present on the surface of the fruit, causing the fresh fruit to overripe.

Question 16

Based on the findings presented above, combined with what you have learned about the hypersensitive respons sequence of events occurs when a pathogen infects a plant cell? Only some of the events will be used)
1) The R protein binds to the avr protein.
2) The pathogen releases avr proteins.
3) The plant cell produces nitric oxide.
4) The pathogen produces reactive oxygen intermediates.
5) A signal transduction cascade occurs.
6) The plant cell and the pathogen die.
7) The pathogen dies, the plant cell lives.
8) The plant cell produces both nitric oxide and reactive oxygen intermediates.

Accepted Answer

A)  2, 1, 5, 8, 6 
B)  1, 5, 4, 3, 7 
C)  2, 3, 4, 5, 7 
D)  2, 5, 4, 3, 6 
E)  1, 5, 8, 2, 7 
A)  2, 1, 5, 8, 6 
B)  1, 5, 4, 3, 7 
C)  2, 3, 4, 5, 7 
D)  2, 5, 4, 3, 6 
E)  1, 5, 8, 2, 7

Question 17

Suppose a plant had a photosynthetic pigment that absorbed far- red wavelengths of light. In which of the following environments could that plant thrive?

Accepted Answer

A)  on the floor of a lake, whose water contains abundant green algae 
B)  on the ocean floor, in very deep waters 
C)  on the forest floor, beneath a canopy of taller plants 
D)  on mountaintops, closer to the Sun 
A)  on the floor of a lake, whose water contains abundant green algae 
B)  on the ocean floor, in very deep waters 
C)  on the forest floor, beneath a canopy of taller plants 
D)  on mountaintops, closer to the Sun

Question 18

Antisense gene sequences can be used to block the transcription of specific genes in a cell or group of cells. Suppose you took a cutting from a plant and treated it with an antisense gene that would block the transcription of an enzyme involved in auxin production. What would happen to your cutting?

Accepted Answer

A)  It would grow to be very tall and thin. 
B)  Photosynthesis would decrease. 
C)  It would not be able to initiate a hypersensitive response. 
D)  Adventitious root growth would be greatly reduced. 
E)  Further differentiation of xylem and phloem would occur. 
A)  It would grow to be very tall and thin. 
B)  Photosynthesis would decrease. 
C)  It would not be able to initiate a hypersensitive response. 
D)  Adventitious root growth would be greatly reduced. 
E)  Further differentiation of xylem and phloem would occur.

Question 19

What do abscisic acid and gibberellins have in common?

Accepted Answer

A)  They both induce the formation of transcription factors that bind to the a- amylase promoter. 
B)  They work together to induce germination by triggering the metabolism of endosperm nutrients. 
C)  They bind to the same cell- surface receptor on cells of the aleurone layer in seeds. 
D)  They are both released from roots to signal drought to the leaves and stimulate the opening of stomata. 
A)  They both induce the formation of transcription factors that bind to the a- amylase promoter. 
B)  They work together to induce germination by triggering the metabolism of endosperm nutrients. 
C)  They bind to the same cell- surface receptor on cells of the aleurone layer in seeds. 
D)  They are both released from roots to signal drought to the leaves and stimulate the opening of stomata.

Question 20

Species from sunny habitat (Chenopodium)

Species from shady habitat (Teucrium)
   Figure 37.1
-The data in the figure above were taken from a study on the effects of far- red light on stem elongation. The data indicate that plants from shady habitats do not respond to far- red light by growing taller. Which of the following would be a logical hypothesis for why these plants do not respond to far- red light?

Accepted Answer

A)  The shade plants do not have protein kinases. 
B)  The shade plants do not have phytochrome. 
C)  The shade plants do not have phototropin. 
D)  The shade plants do not have cryptochromes. 
E)  All of these are reasonable hypotheses. 
A)  The shade plants do not have protein kinases. 
B)  The shade plants do not have phytochrome. 
C)  The shade plants do not have phototropin. 
D)  The shade plants do not have cryptochromes. 
E)  All of these are reasonable hypotheses.

Exam 37: Plant Sensory Systems, Signals, and Responses

The addition of a phosphate group to a protein is called _ _, and it usually results in .

What do phototropin and ABA have in common?

Which of the following is the strongest evidence that cytokinins regulate cell divisions?

Upon exposure to blue light, plants not only begin to grow toward the light, but move their chloroplasts to the sunny side of each cell. Why would it be advantageous to move chloroplasts within cells?

Why does auxin move through the plant slower than sucrose does?

A caterpillar eats a leaf of a plant. The next day it crawls to a nearby leaf to eat. But after eating the second leaf, the caterpillar gets very sick and falls off the plant. Which of the following molecules were involved in the plant's ability to defend itself against the second attack?

Which of the following events would be initially triggered by a signal transduction cascade?

You discover a chemical that inhibits the conversion of starch to sugar and inhibits the breakdown of chlorophyll and cellulose in fruit. Who might be interested in buying this chemical?

You have a bush in your yard that is the height that you want it, but not as bushy as you want it to be. How can you prune it to trigger it to get bushier?

If you wanted to genetically engineer a plant to be more resistant to attack by pathogenic bacteria and viruses, which of the following hormones would you manipulate?

You buy some fresh fruit at the grocery store. When you get home, you are in a hurry, and you put the fresh fruit in the crisper with some overripe fruit. At the end of the week you are disappointed to find that your new fruit has already become overripe. What happened?

Suppose a plant had a photosynthetic pigment that absorbed far- red wavelengths of light. In which of the following environments could that plant thrive?

What do abscisic acid and gibberellins have in common?

Biology and the Tree of Life

Water and Carbon: the Chemical Basis of Life

Protein Structure and Function

Nucleic Acids and the Rna World

An Introduction to Carbohydrates

Lipids, Membranes, and the First Cells

Inside the Cell

Energy and Enzymes

Cellular Respiration and Fermentation

Photosynthesis

Cellcell Interactions

The Cell Cycle

Meiosis

Mendel and the Gene

Dna and the Gene: Synthesis and Repair

How Genes Work

Transcription, Rna Processing, and Translation

Control of Gene Expression in Bacteria

Control of Gene Expression in Eukaryotes

The Molecular Revolution: Biotechnology and Beyond

Gene Structure and Development

Evolution by Natural Selection

Evolutionary Processes

Speciation

Phylogenies and the History of Life

Bacteria and Archaea

Protists

Green Algae and Land Plants

Fungi

An Introduction to Animals

Protostome Animals

Deuterostome Animals

Viruses

Plant Form and Function

Water and Sugar Transport in Plants

Plant Nutrition

Plant Reproduction and Development

Animal Form and Function

Water and Electrolyte Balance in Animals

Animal Nutrition

Gas Exchange and Circulation

Animal Nervous Systems

Animal Sensory Systems

Animal Movement

Chemical Signals in Animals

Animal Reproduction and Development

The Immune System in Animals

An Introduction to Ecology

Behavioural Ecology

Population Ecology

Community Ecology

Ecosystems and Global Ecology

Biodiversity and Conservation Biology

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