Question 1

Where is the growth-promoting substance that promotes stem elongation and bending toward light primarily produced?

Accepted Answer

A)   in root tips, travelling to the stem in the xylem
B)   in the centre of the stem region where elongation or bending occurs
C)   in flowers and flower buds
D)   in the shoot tip D

Question 2

Which of the following are chaperone-type proteins that stabilize other proteins in response to environmental stresses such as salinity, drought, heat, and cold?

Accepted Answer

A)   phytoalexins
B)   PR proteins
C)   heat-shock proteins
D)   R genes C

Question 3

Which hormone's reduction in its amount causes a bush to become more bushy (have more lateral growth) after trimming a shrub?

Accepted Answer

A)   auxin
B)   ethylene
C)   abscisic acid
D)   gibberellin A

Question 4

Specific cells in developing seeds and maturing fruits have receptors for ethylene, but cells in stems generally do not.

Accepted Answer

A) True 
 B)False

Question 5

Which plant hormones cause chloroplasts to mature?

Accepted Answer

A)   cytokinins
B)   salicylic acids
C)   abscisic acids
D)   ethylenes

Question 6

Which of the following would probably NOT promote dormancy in at least some plants?

Accepted Answer

A)   nitrogen deficiency
B)   long nights
C)   cold nights
D)   warm nights

Question 7

Which type of plant signalling molecule is similar in structure to aspirin?

Accepted Answer

A)   abscisic acid
B)   ethylene
C)   salicylic acid
D)   jasmonate

Question 8

An agar block filled with auxin is placed on top of a shoot that has had the shoot tip removed. The agar block is placed so that it covers only one side of the top of the shoot. Which of the following should occur?

Accepted Answer

A)   The shoot will stop growing.
B)   The shoot will grow faster on the side with the agar block.
C)   The shoot will grow straight up.
D)   The shoot will grow faster on the side away from the agar block.

Question 9

Explain the hypersensitive response.

Accepted Answer

The answer of Explain the hypersensitive response....

Question 10

Choose the type of plant chemical or its action most closely associated with the consequence listed below. Each chemical or action may be used more than once.
-operating in systemic acquired resistance

Accepted Answer

A)  jasmonates
B)  salicylic acid
C)  phytoalexins
D)  "antifreeze proteins"
E)  oligosaccharinsF) PR proteinsG) systemin

Question 11

Placing a ripe apple with other apples that are not ripe will cause the other apples to ripen sooner. Which type of plant hormone is responsible for this effect?

Accepted Answer

A)   brassinosteroid
B)   ethylene
C)   auxin
D)   oligosaccharin

Question 12

When a plant becomes infected by pathogenic bacteria or fungi, it may respond by way of a fight or flight response-a defence that cordons off an infection site surrounding it with dead cells.

Accepted Answer

A) True 
 B)False

Question 13

Suppose you are culturing tobacco in a petri dish at a 10:1 ratio of auxin to cytokinin. What would you do in order to promote only shoot development?

Accepted Answer

A)   increase the cytokinin ratio
B)   increase the auxin ratio
C)   reduce the auxin level significantly and increase the cytokinin level slightly
D)   grow the tobacco in the dark

Question 14

What are the usual concentrations of plant hormones that are effective, and what kind of effects do they have on different plant tissues?

Accepted Answer

A)   They are effective only in extremely large concentrations, and they have the same effect on different plant tissues.
B)   They are effective at low concentrations, and they have different effects on different plant tissues.
C)   They are effective at low concentrations, and they have the same effect on different plant tissues.
D)   They are effective only in extremely large concentrations, and they have different effects on different plant tissues.

Question 15

Choose the type of plant chemical or its action most closely associated with the consequence listed below. Each chemical or action may be used more than once.
-synthesizing defensive chemicals

Accepted Answer

A)  jasmonates
B)  salicylic acid
C)  phytoalexins
D)  "antifreeze proteins"
E)  oligosaccharinsF) PR proteinsG) systemin

Question 16

What do we call plant responses to the relative lengths of light and dark periods in their environment during each 24-hour period?

Accepted Answer

A)   gravitropisms
B)   photoperiodisms
C)   thigmotropisms
D)   phototropisms

Question 17

Which type of plant hormone has been shown to both promote pollen tube elongation and inhibit root elongation?

Accepted Answer

A)   jasmonate
B)   ethylene
C)   brassinosteroid
D)   salicylic acid

Question 18

Where is the auxin receptor ABP1 located in plant cells?

Accepted Answer

A)   in the plasma membrane
B)   in the cytoplasm
C)   in the endoplasmic reticulum
D)   in the cell wall

Question 19

Which of the following serves as a switching mechanism in the photoperiodic response in plants?

Accepted Answer

A)   phytochrome
B)   auxin
C)   cryptochrome
D)   calmodulin

Question 20

Where are abscisic acid receptors located in plant cells?

Accepted Answer

A)   in the cell wall
B)   in the cytoplasm
C)   in the endoplasmic reticulum
D)   in the plasma membrane

Exam 37: Plant Signals and Responses to the Environment