Deck 30: Communication Strategies in Plants

Question 1

Which plant compound is most likely responsible for the unusual absence of heart disease among the Kuna?​

A) ​curcumin
B) ​strigolactone
C) ​resveratrol
D) ​caffeine
E) ​epicatechin

Answer 1

E

Question 2

2,4-D, a potent eudicot weed killer, is most likely a synthetic ____.

A) ​auxin
B) ​gibberellin
C) ​cytokinin
D) ​phytochrome
E) brassinosteroid

Answer 2

A

Question 3

Gibberellin stimulates ____.

A) ​fruit ripening
B) ​leaf abscission
C) ​lateral root formation
D) ​stem lengthening between the nodes
E) ​stem lengthening at the tip

Answer 3

D

Question 4

Perhaps a plant's greatest liability is its inability to ____.

A) ​produce growth hormones
B) ​use aerobic respiration
C) ​move when conditions around it deteriorate
D) ​produce its own lipids and proteins
E) ​respond to dwindling supplies of nutrients and water

Question 5

A hormonal signal is detected by ____.

A) ​chloroplasts
B) ​transport proteins
C) ​receptor proteins
D) ​statoliths
E) ​plasma membranes

Question 6

Apical dominance is an effect that causes ____.

A) ​a directional adjustment of growth in response to environmental stimuli
B) ​leaves and other plant parts to fall off, or senesce
C) ​roots to lengthen while inhibiting shoot growth
D) ​lateral buds to become active when a shoot is lengthening at its tip
E) ​lateral buds to stay dormant when a shoot is lengthening at its tip

Question 7

Root formation in stem cuttings can be improved by the application of ____.

A) ​synthetic auxins
B) ​abscisic acid
C) ​salicylic acid
D) ​ethylene
E) ​gibberellin

Question 8

The plant hormone that promotes dormancy in some plants and seeds is ____.

A) ​abscisic acid
B) ​auxin
C) ​gibberellin
D) ​ethylene
E) ​cytokinin

Question 9

A ____ is an extracellular signaling molecule that exerts its effect at very low concentrations.

A) ​statolith
B) ​protein receptor
C) ​plant hormone
D) ​cytochrome
E) ​phytochrome

Question 10

In most cases, the term auxin refers to ____.

A) ​abscisic acid
B) ​indole-3-acetic acid
C) ​jasmonic acid
D) ​nitric oxide
E) ​salicylic acid

Question 11

If a shoot's tip breaks off, ____ moves into lateral buds and stimulates cell divisions.

A) ​auxin
B) ​gibberellin
C) ​cytokinin
D) ​abscisic acid
E) ​ethylene

Question 12

Plants make ____, which are similar to female sex hormones in mammals but have nothing to do with sexual reproduction in plants.

A) ​estrogens
B) ​phytoestrogens
C) ​auxins
D) ​cytokinins
E) ​gibberellins

Question 13

When a hormone inhibits its own expression, it is called a ____.

A) ​hormone stimulant
B) ​hormone coordinator
C) ​hormone suppressant
D) ​negative feedback loop
E) ​positive feedback loop

Question 14

The Kuna tribe, which inhabits islands off the coast of Panama, has almost no incidence of heart disease due to ____.

A) ​the unusually large amount of cocoa they consume
B) ​the unusually small amount of red wine they consume
C) ​the unusually large amount of coffee they consume
D) ​the absence of disease-carrying mosquitoes on the islands
E) ​an allele that is unique to their tribe

Question 15

Which of the following is mismatched?

A) ​cytokinin - inhibits lateral root formation
B) ​auxin - promotes cell elongation
C) ​gibberellin - involved in phototropism and gravitropism
D) ​abscisic acid - promotes stomatal closure
E) ​ethylene - promotes leaf abscission

Question 16

Temperature extremes, lack of water, and other environmental stresses trigger an increase in ____ synthesis, release, and transport, which helps the plant survive the adverse conditions.

A) ​cytokinin
B) ​gibberellin
C) ​auxin
D) ​abscisic acid
E) ​ethylene

Question 17

The gaseous plant hormone is ____.

A) ​auxin
B) ​gibberellin
C) ​cytokinin
D) ​abscisic acid
E) ​ethylene

Question 18

The plant hormone that promotes fruit ripening is ____.

A) auxin​
B) ​gibberellin
C) ​cytokinin
D) ​abscisic acid
E) ​ethylene

Question 19

Auxin is made mainly in ____ and in young leaves, and transported elsewhere.

A) ​chloroplasts
B) ​lateral buds
C) ​lateral meristems
D) ​root apical meristems
E) ​shoot apical meristems

Question 20

Synthetic auxin can be used as a(n) ____.

A) ​pesticide
B) ​herbicide
C) ​fungicide
D) ​insecticide
E) ​bacteriocide

Question 21

Figure 30.19C

Which plant hormone listed below is responsible for the symbiotic relationship shown in the accompanying figure?​

A) ​auxin
B) ​gibberellin
C) ​cytokinin
D) ​jasmonic acid
E) ​abscisic acid

Question 22

A houseplant placed in a window grows toward the source of light because auxin ____.

A) ​becomes more concentrated on the illuminated side of the plant
B) ​becomes more concentrated in the roots of the plant
C) ​becomes more concentrated on the shady side of the plant
D) ​inhibits the growth of cells on the shady side, so the cells on the sunny side grow larger
E) ​inhibits the growth of cells on the shady side, so the cells on the sunny side grow faster

Question 23

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
abscisic acid

Question 24

The requirement of cold weather before a particular plant process occurs (e.g., germination) is knownas ____.

A) ​the biological clock
B) ​vernalization
C) ​photoperiodism
D) ​biennial life cycle
E) ​perennial life cycle

Question 25

Gravity-sensing mechanisms of many organisms are based on ____.

A) ​spicules
B) ​statoliths
C) ​uric acid crystals
D) ​sclereids
E) ​nematocysts

Question 26

Even though the autumn may be unusually warm, the leaves from deciduous trees begin to drop during September. Which of the following is the best explanation?​

A) ​The trees are responding to shorter days.
B) The autumn months are usually wetter because the summer rains were delayed.​
C) ​The effects of phototropism are operating "right on schedule."
D) ​There is not enough sunlight to carry on photosynthesis any longer.
E) ​The trees are responding to consistent temperatures.

Question 27

The effect of directional growth shown in the accompanying figure is known to be caused by ____.

A) ​thigmotropism
B) ​gravitropism
C) ​abscisic acid
D) ​salicylic acid
E) ​vernalization

Question 28

In trees, such as the horse chestnut, the abscission of leaves and fruits in the fall is mediated by ____.

A) ​abscisic acid
B) ​auxin
C) ​ethylene
D) ​cytokinin
E) ​gibberellin

Question 29

Cycles of biological activity that are repeated every 24 hours are called ____.

A) ​systemic acquired rhythms
B) ​tropisms
C) ​physiological requirements
D) ​circadian rhythms
E) ​photoperiods

Question 30

The mechanism that causes a vine's tendrils to grow around an object, such as a wire fenceline, is called ____.

A) ​thigmotropism
B) ​phototropism
C) ​gravitropism
D) ​vernalization
E) ​photoperiodism

Question 31

Photoperiodism is the ____.

A) ​duration of flowering in a plant
B) ​amount of light needed by a plant to exhibit normal growth
C) ​response of a plant to the duration of light and darkness
D) ​light phase of photosynthesis during which photolysis of water occurs
E) ​opposite of photorespiration

Question 32

Deciduous trees in North America are dormant during winter months because ____.

A) ​they receive no precipitation during winter
B) ​photosynthesis cannot occur during winter
C) ​this offers a way to survive the extended drought-like conditions
D) ​the cold temperatures would otherwise damage leaves and buds
E) ​they have no leaves during winter months

Question 33

The pigment most involved with photoperiodism is ____.

A) ​chlorophyll
B) ​xanthophyll
C) ​anthocyanin
D) ​phytochrome
E) ​phytoerythrin

Question 34

Downward bending of a seedling root can be blocked by ____.

A) ​moving it to a dark room
B) ​auxin transporters
C) ​auxin transport inhibitors
D) ​mutations in genes that code for auxin transport proteins
E) ​auxin transport inhibition and mutations in genes that code for auxin transport proteins

Question 35

A directional adjustment of growth in response to environmental stimuli is called ____.

A) ​circadian rhythm
B) ​vernalization
C) ​photoperiodism
D) ​statolith
E) ​tropism

Question 36

A plant secretes ____ when it needs to respond defensively to a pathogen.

A) ​salicylic acid
B) ​systemin
C) ​brassinosteroids
D) ​mineralocorticoids
E) ​nitric oxide

Question 37

Irises and other ____ plants flower only when the hours of darkness fall below a critical value, typically in summer.

A) short-day
B) ​long-day
C) ​annual
D) ​biennial
E) ​perennial

Question 38

The flowers of plants pollinated by night-flying bats open, secrete nectar, and release fragrance only at night. The mechanism that controls this is called ____.

A) ​thigmotropism
B) ​heliotropism
C) ​phototropism
D) ​photoperiodism
E) ​circadian rhythm

Question 39

Phytochrome is converted from the inactive to the active form by being exposed to light of what color?

A) ​far red
B) ​red
C) ​yellow
D) ​blue
E) ​violet

Question 40

The plant movement in the accompanying figure is caused by ____.

A) ​auxin differences in two sides of the stems
B) ​gibberellin released in one side of the leaf
C) ​abscisic acid in two sides of the stems
D) ​salicylic acid in two sides of the roots
E) ​cytokinin differences in two sides of the stem

Question 41

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
epicatechin

Question 42

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
long-day plant

Question 43

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
phototropism

Question 44

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
statolith

Question 45

Respond to the following statements in reference to the five plant hormones listed below.​
a.​auxins
b.​gibberellins
c.​cytokinins
d.​abscisic acid
e.​ethylene
This hormone mediates tropisms.

Question 46

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
circadian rhythm

Question 47

Respond to the following statements in reference to the five plant hormones listed below.​
a.​auxins
b.​gibberellins
c.​cytokinins
d.​abscisic acid
e.​ethylene
This hormone promotes bud and seed dormancy.

Question 48

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
short-day plant

Question 49

The flavonoid called epicatechin, found in cocoa, is probably responsible for the absence of __________ among the Kuna tribe.

Question 50

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
auxin

Question 51

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
gibberellin

Question 52

Respond to the following statements in reference to the five plant hormones listed below.​
a.​auxins
b.​gibberellins
c.​cytokinins
d.​abscisic acid
e.​ethylene
This hormone inhibits formation of lateral roots.

Question 53

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
cytokinin

Question 54

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
vernalization

Question 55

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
photoperiodism

Question 56

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
salicylic acid

Question 57

Respond to the following statements in reference to the five plant hormones listed below.​
a.​auxins
b.​gibberellins
c.​cytokinins
d.​abscisic acid
e.​ethylene
This hormone is a gas that promotes ripening.

Question 58

Respond to the following statements in reference to the five plant hormones listed below.​
a.​auxins
b.​gibberellins
c.​cytokinins
d.​abscisic acid
e.​ethylene
This hormone causes a stem to lengthen between the nodes by inducing cell division and elongation.

Question 59

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
ethylene

Question 60

Choose the one most appropriate answer for each. Each letter will be used once.​
a.​growth response that orients parts of a plant in a direction influenced by light
b.​plays a critical role in apical dominance
c.​an organism's response to changes in length of day relative to night
d.​organelle involved in sensing gravity
e.​light-sensitive pigment that helps set plant circadian rhythm based on length of night
f.​low-temperature stimulation of flowering
g.​closes stomata in times of stress
h.​stimulates fruit ripening
i.​flowers only when hours of darkness fall below a critical value
j.​flavonoid in cocoa responsible for the unusual absence of heart disease in the Kuna
k.​occurring on a 24-hour cycle
l.​flowers only when hours of darkness are greater than some critical value
m.​activates systemic acquired resistance
n.​stimulates growth of lateral buds
o.​mobilizes food reserves in germinating seeds
phytochrome

Question 61

If a shoot's tip breaks off, its source of auxin disappears, so the __________ level rises in the stem.

Question 62

A mutant plant is found in which the seeds germinate far too early. Which hormone is likely involved and why?

Question 63

In some plants, the direction of growth changes in response to contact with an object. This is called __________.

Question 64

Explain what occurs when a plant exhibits heliotropism.

Question 65

Abscisic acid promotes bud and seed __________, and it limits water loss by promoting stomatal closure.

Question 66

During primary growth, auxin causes young cells to expand by increasing the activity of __________ that pump hydrogen ions from cytoplasm into the cell wall.

Question 67

When a shoot is lengthening at the tip, its lateral buds are usually dormant, an effect called __________.

Question 68

What technique could a gardener use to invoke the growth of lateral buds on a plant, thereby making the plant bushier?

Question 69

__________ refers to an organism's response to changes in the length of day relative to night.

Question 70

In the root apical meristem, __________ supports division of undifferentiated meristem cells, and cytokinin signals the cells to differentiate.

Question 71

Explain how gibberellin "removes the brakes" from some cellular processes.

Question 72

Farmers spray seedless grape plants with synthetic __________, which increases the size of the resulting fruit.

Question 73

A(n) __________ is an extracellular signaling molecule that exerts its effect at very low concentrations.