Questão 1
Questão
The detector of light during de-etiolation (greening) of a tomato plant is (are) ________.
Responda
-
A) carotenoids
-
B) xanthophylls
-
C) phytochrome
-
D) auxin
Questão 2
Questão
Plant hormones ________.
Responda
-
A) in plant cells naturally exist in very large amounts
-
B) change their shape in response to stimulus
-
C) are unable to move from one cell to another
-
D) affect only cells with the appropriate receptor
Questão 3
Questão
Which of the following mechanisms is the correct sequence of events that takes place during the plant responses to internal and external signals?
Responda
-
A) transduction, reception, and response
-
B) reception and transduction
-
C) reception, transduction, and response
-
D) reception and response
Questão 4
Questão
Which of the following mechanisms is in the correct sequence of steps (I-IV as listed below) that takes place during the formation of de-etiolation (greening) response proteins in plants?
I. Detection of light signal
II. Activation of phytochrome
III. Activation of specific protein kinase1
IV. Formation of de-etiolation response protein
Responda
-
A) I, III, II, and IV
-
B) I, II, III, and IV
-
C) II, I, III, and IV
-
D) III, I, II, and IV
Questão 5
Questão
Which of the following can function in signal transduction in plants?
I. calcium ions
II. nonrandom mutations
III. receptor proteins
IV. autochrome
V. secondary messengers
Responda
-
A) only I, III, and IV
-
B) only I, II, and V
-
C) only I, III, and V
-
D) only II, III, and V
Questão 6
Questão
Plant hormones produce their effects by ________.
I. altering the expression of genes
II. modifying the permeability of the plasma membrane
III. modifying the structure of the nuclear envelope membrane
Responda
-
A) only I
-
B) only II
-
C) only III
-
D) only I and II
Questão 7
Questão
Plant hormonal regulation differs from animal hormonal regulation in that ________.
Responda
-
A) there are no dedicated hormone-producing organs in plants as there are in animals
-
B) all production of hormones is local in plants with little long-distance transport
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C) only animal hormone concentrations are developmentally regulated
-
D) only animal hormones may have either external or internal receptors
Questão 8
Questão
Auxins in plants are known to affect which of the following processes?
I. gravitropism of shoots
II. maintenance of seed dormancy
III. phototropism of shoots
IV. inhibition of lateral buds
V. apical dominance
Responda
-
A) only I and II
-
B) only I, III, and V
-
C) only I, III, IV, and V
-
D) only II, III, IV, and V
Questão 9
Questão
Experiments on the positive phototropic response of plants indicate that ________.
Responda
-
A) light destroys auxin
-
B) auxin moves down the plant apoplastically
-
C) auxin is synthesized in the area where the stem bends
-
D) auxin can move to the shady side of the stem
Questão 10
Questão
What are the primary sites of auxin (IAA) production in plants?
Questão 11
Questão
What are the primary sites of ethylene production in high concentrations in plants?
Questão 12
Questão
Which one of the following hormones regulates cell division in plants?
Responda
-
A) auxin (IAA)
-
B) ethylene
-
C) gibberellins
-
D) cytokinins
Questão 13
Questão
Which one of the following hormones stimulates stem elongation and pollen tube growth?
Responda
-
A) auxin (IAA)
-
B) ethylene
-
C) gibberellins
-
D) cytokinins
Questão 14
Questão
Generally, each hormone has multiple functions in plants depending on ________.
I. site of action
II. its concentration
III. developmental stage
IV. age
Responda
-
A) I, II, III, and IV
-
B) I, II, and III
-
C) I and II
-
D) II
Questão 15
Questão
Apical dominance in plants is under the control of ________.
Questão 16
Questão
Arrange the following steps that occur during drought tolerance in plants in a correct sequence.
I. hormone ABA accumulation in the leaves
II. causes stomata to close
III. reduction in transpiration
IV. preventing further water loss
Responda
-
A) I, II, III, and IV
-
B) I, III, II, and IV
-
C) II, I, III, and IV
-
D) III, I, II, and IV
Questão 17
Questão
Which of the following statements best summarizes the acid growth hypothesis in an actively growing shoot?
Responda
-
A) Auxin stimulates proton pumps in the plasma membrane and tonoplast.
-
B) Auxin-activated proton pumps lower the pH of the cell wall, which breaks bonds and makes the walls more flexible.
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C) Auxins and gibberellins together act as a lubricant to help stretch cellulose microfibrils.
-
D) Auxins activate aquaporins that increase turgor pressure in the cells.
Questão 18
Questão
Which of the following conclusions is supported by the research of both Peter Boysen-Jensen and Charles and Francis Darwin on shoot responses to light?
Responda
-
A) When shoots are exposed to light, a chemical substance migrates toward the light.
-
B) A chemical substance involved in shoot bending is produced in shoot tips.
-
C) Once shoot tips have been cut, normal growth cannot be induced.
-
D) Light stimulates the synthesis of a plant hormone that responds to light.
Questão 19
Questão
An eccentric millionaire botanist has offered a $25,000 scholarship to anyone who can successfully get a plant to grow through a vertical maze in complete darkness. The maze is not in a box; the maze is simply drawn on the wall, and the contestants must get their plant to grow in a pattern that matches the path through the maze. You need the money and feel confident that you can accomplish this task. Which of the following techniques will help you succeed?
Responda
-
A) Apply auxin directly to the shoot tip on the side to which you want the tip to bend.
-
B) Apply auxin directly to the part of the stem just below the tip opposite from the direction you want the stem to bend.
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C) Inject compounds that block auxin receptors into the part of the stem opposite from the direction you want the stem to bend.
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D) Plant the roots in two different pots, and apply auxin to the root bucket that is on the same side as the direction you want the plant to bend.
Questão 20
Questão
You have a small tree in your yard that is the height that you want it, but does not have as many branches as you want. How can you prune it to trigger it to increase the number of branches?
Responda
-
A) Cut off the leaves at the ends of several branches.
-
B) Cut off the tips of the main shoots.
-
C) Cut off lower branches.
-
D) Cut off the leaves at the base of most of the branches.
Questão 21
Questão
) As cytokinins are primarily produced in roots, what route would they travel to influence lateral shoot formation in a recently topped tree?
Responda
-
A) symplastic
-
B) tracheids/vessels
-
C) phloem
-
D) apoplastic
Questão 22
Questão
Who might be interested in using cytokinins?
Responda
-
A) grocers, to spray on fruit to enhance ripening in the store
-
B) consumers, to spray on fruit before eating to enhance taste
-
C) florists, to dip stems in to keep leaves green longer
-
D) farmers, to spray on fruit after picking to stall ripening
Questão 23
Questão
If a farmer wanted more loosely packed clusters of grapes, he would most likely spray the immature bunches with ________.
Responda
-
A) auxin
-
B) gibberellins
-
C) cytokinins
-
D) abscisic acid
Questão 24
Questão
________ prevents seeds from germinating until conditions are favorable for the growth of the plant.
Responda
-
A) Ethylene
-
B) Zeaxanthin
-
C) Gibberellin
-
D) Abscisic acid
Questão 25
Questão
A population of plants experiences several years of severe drought. Much of the population dies due to lack of water, but a few individuals survive. You set out to discover the physiological basis for their adaptation to such an extreme environmental change. You hypothesize that the survivors have the ability to synthesize higher levels of ________ than their siblings do
Responda
-
A) auxin
-
B) gibberellin
-
C) cytokinin
-
D) abscisic acid
Questão 26
Questão
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?
Responda
-
A) carbon dioxide
-
B) cytokinins
-
C) ethylene
-
D) auxin
Questão 27
Questão
In the fall, the leaves of some trees change color. This happens because chlorophyll breaks down and the accessory pigments become visible. What hormone is responsible for this?
Responda
-
A) phototropin
-
B) abscisic acid
-
C) cytokinin
-
D) ethylene
Questão 28
Questão
Which type of mutant would be most likely to produce a bushier phenotype?
Responda
-
A) auxin overproducer
-
B) strigolactone overproducer
-
C) cytokinin underproducer
-
D) strigolactone underproducer
Questão 29
Questão
Vines in tropical rain forests must grow toward large trees before being able to grow toward the sun. To reach a large tree, the most useful kind of growth movement for a tropical vine presumably would be ________.
Questão 30
Questão
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. The adaptive advantage of moving chloroplasts to the sunny side of each cell ________.
Responda
-
A) maximizes light absorption by the chloroplasts for photosynthesis
-
B) increases production of phototropic hormones
-
C) maximizes heat absorption by the chloroplasts for cellular respiration
-
D) increases adenosine triphosphate (ATP) production during the light-independent reactions
Questão 31
Questão
Mammalian eyes sense light because the photoreceptor cells have molecules called opsins, which change structure when exposed to light. Which of the following plant molecules would be analogous to mammalian opsins in their light-sensing ability?
Questão 32
Questão
Seed packets give a recommended planting depth for the enclosed seeds. The most likely reason some seeds are to be covered with only 1/4 inch of soil is that the ________.
Responda
-
A) seedlings do not have an etiolation response
-
B) seeds require light to germinate
-
C) seeds require a higher temperature to germinate
-
D) seeds are very sensitive to waterlogging
Questão 33
Questão
Suppose a plant had a photosynthetic pigment that absorbed far-red wavelengths of light. In which of the following environments could that plant thrive?
Responda
-
A) on the surface of a lake
-
B) on the forest floor, beneath a canopy of taller plants
-
C) on the ocean floor, in very deep waters
-
D) on mountaintops, closer to the Sun
Questão 34
Questão
The biological clock controlling circadian rhythms must ultimately ________.
Responda
-
A) depend on environmental cues
-
B) affect gene transcription
-
C) stabilize on a 24-hour cycle
-
D) speed up or slow down with increasing or decreasing temperature
Questão 35
Questão
Which of the colors of visible light induces curvature in coleoptile most effectively?
Responda
-
A) red
-
B) blue
-
C) violet
-
D) orange
Questão 36
Questão
Phytochrome plays a critical role in seed germination. Which of the colors maximizes the seed germination?
Responda
-
A) red
-
B) blue
-
C) violet
-
D) orange
Questão 37
Questão
Many plants flower in response to day-length cues. Which of the following statements best summarizes this phenomenon?
Responda
-
A) As a rule, short-day plants flower in the summer.
-
B) As a rule, long-day plants flower in the spring or fall.
-
C) Long-day plants flower in response to long days, not short nights.
-
D) Flowering in short-day and long-day plants is controlled by phytochrome.
Questão 38
Questão
Plants often use changes in day length (photoperiod) to trigger events such as dormancy and flowering. It is logical that plants have evolved this mechanism because photoperiod changes ________.
Responda
-
A) are more predictable than air temperature changes
-
B) predict moisture availability
-
C) are modified by soil temperature changes
-
D) can reset the biological clock
Questão 39
Questão
A gardener in Canada wants to surprise his mother on her birthday and make her favorite hibiscus bush flower in May instead of at the end of June. The bush is growing in the greenhouse. Which of the following might make the hibiscus bush flower early?
Responda
-
A) grafting leaves of a hibiscus that was exposed to long nights
-
B) grafting leaves of a hibiscus that was exposed to short nights
-
C) exposing flower buds of the hibiscus bush to long nights
-
D) exposing flower buds of the hibiscus bush to short nights
Questão 40
Questão
Which of the following environmental factors can be sensed by plants?
I) gravity
II) pathogens
III) wind
IV) light
Responda
-
A) only I and III
-
B) only I, II, and IV
-
C) only II, III, and IV
-
D) I, II, III, and IV
Questão 41
Questão
Shoots that grow vertically toward the sun can be characterized as ________.
Responda
-
A) positive for phototropism and negative for gravitropism
-
B) neutral for phototropism and positive for gravitropism
-
C) negative for phototropism and positive for gravitropism
-
D) positive for phototropism and neutral for gravitropism
Questão 42
Questão
The rapid leaf movements resulting from a response to touch (thigmotropism) primarily involve ________.
Responda
-
A) potassium channels
-
B) nervous tissue
-
C) aquaporins
-
D) stress proteins
Questão 43
Questão
In extremely cold regions, woody species may survive freezing temperatures by ________.
Responda
-
A) emptying water from the vacuoles to prevent freezing
-
B) decreasing the numbers of phospholipids in cell membranes
-
C) decreasing the fluidity of all cellular membranes
-
D) increasing cytoplasmic levels of specific solute concentrations, such as sugars
Questão 44
Questão
Most scientists agree that global warming is underway; 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?
Responda
-
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
Questão 45
Questão
When an arborist prunes a limb off a valuable tree, he or she may paint the cut surface. The primary purpose of the paint is to ________.
Responda
-
A) minimize water loss by evaporation from the cut surface
-
B) improve the appearance of the cut surface
-
C) stimulate growth of the cork cambium to "heal" the wound
-
D) block entry of pathogens through the wound
Questão 46
Questão
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) ________.
Questão 47
Questão
Generalized defense responses in organs distant from the infection site are called ________.
Questão 48
Questão
A particular species of virus carries a gene for salicylate hydroxylase, an enzyme that breaks down salicylic acid. Will this virus be more or less virulent to plants than other viruses?
Responda
-
A) more virulent
-
B) less virulent
-
C) same virulent
-
D) faster virulent
Questão 49
Questão
Which event during the evolution of land plants favored the synthesis of secondary compounds?
Responda
-
A) the greenhouse effect throughout the Devonian period
-
B) the reverse-greenhouse effect during the Carboniferous period
-
C) the association of the roots of land plants and fungi
-
D) the rise of herbivory
Questão 50
Questão
For a plant to initiate chemical responses to herbivory, before it is directly affected by herbivores, ________.
Responda
-
A) a plant must have already flowered at least once
-
B) volatile "signal" compounds must be perceived
-
C) gene-for-gene intraspecific recognition must occur
-
D) phytoalexins must be released
Questão 51
Questão
You may have observed plants rotate towards a light source, thereby increasing the plant's ability to intercept light energy and increase photosynthesis. You, however, are given the task of preventing grass seedlings from rotating toward the light. Using your knowledge of phototropism, which of the following experimental procedures would you use to complete your task?
Responda
-
A) Cover the growing tip of the grass seedling with black paper.
-
B) Supply the seedlings with very dim light (red light does not induce a bend).
-
C) Cover the portion of the seedling below the tip with a black shield.
-
D) Supply the seedling with nutrient-rich fertilizer solution.
Questão 52
Questão
A plant scientist was hired by a greenhouse operator to devise a way to force iris plants to bloom in the short days of winter. Iris normally blooms as a long-day (short-night) plant. Which of the following has the best chance of creating iris blooms in winter?
Responda
-
A) Artificially increase the period of darkness in the greenhouse.
-
B) Increase the temperature to more closely follow summer temperatures.
-
C) Alternate four hours of darkness with four hours of light repeatedly over each 24-hour period.
-
D) Interrupt the long winter nights with a brief period of light.
Questão 53
Questão
An individual plant was discovered that could not grow towards light. After some research, it was determined that the reason was a defective gene that did not allow for the level of cell elongation necessary for a phototropic response. This mutation greatly reduces the fitness of the individual plant. Which reason best describes the reason for the loss of fitness?
Responda
-
A) The plant was too short to attract insects for pollination.
-
B) The plant could not adjust to directional light, which reduced photosynthetic activity and therefore energy available for reproduction.
-
C) Because the plant grew much taller and straighter, resources that could be used for reproduction were used for growth.
-
D) The loss of a phototropic response meant that the plant's seeds could not germinate, so reproduction would be unsuccessful.
Questão 54
Questão
The hormone that helps plants respond to drought is
Responda
-
A) auxin.
-
B) abscisic acid.
-
C) cytokinin.
-
D) ethylene.
Questão 55
Questão
Auxin enhances cell elongation in all of these ways except
Questão 56
Questão
Charles and Francis Darwin discovered that
Responda
-
A) auxin is responsible for phototropic curvature.
-
B) red light is most effective in shoot phototropism.
-
C) light destroys auxin.
-
D) light is perceived by the tips of coleoptiles.
Questão 57
Questão
How may a plant respond to severe heat stress?
Responda
-
A) by reorienting leaves to increase evaporative cooling
-
B) by creating air tubes for ventilation
-
C) by producing heat-shock proteins, which may protect the plant's proteins from denaturing
-
D) by increasing the proportion of unsaturated fatty acids in cell membranes, reducing their fluidity
Questão 58
Questão
The signaling molecule for flowering might be released earlier than usual in a long-day plant exposed to flashes of
Responda
-
A) far-red light during the night.
-
B) red light during the night.
-
C) red light followed by far-red light during the night.
-
D) far-red light during the day.
Questão 59
Questão
If a long-day plant has a critical night length of 9 hours, which 24-hour cycle would prevent flowering?
Responda
-
A) 16 hours light/8 hours dark
-
B) 14 hours light/10 hours dark
-
C) 4 hours light/8 hours dark/4 hours light/8 hours dark
-
D) 8 hours light/8 hours dark/light flash/8 hours dark
Questão 60
Questão
A plant mutant that shows normal gravitropic bending but does not store starch in its plastids would require a reevaluation of the role of ________ in gravitropism.
Responda
-
A) auxin
-
B) calcium
-
C) statoliths
-
D) differential growth