49. Recent molecular research shows that plant responses to stress involve the same chemical steps as
______ responses to stress.
a.
fungal
b.
amphibian
c.
algal
d.
human
e.
bacterial
50. Which of the following did Nam-Hai Chua and his colleagues demonstrate to be part of the abscisic
acid response pathway?
a.
cyclic ADP-ribose
b.
Ca2+
c.
protein kinases
d.
cyclic ADP-ribose and protein kinases
e.
cyclic ADP-ribose, Ca2+ and protein kinases
51. In some cases, when an insect begins feeding on a leaf the plant responds by activating a signaling
pathway that results in the production of ____, which disrupt an insect’s capacity to digest proteins.
a.
gibberellins
b.
lipases
c.
chitinases
d.
protease inhibitors
e.
cytokinins
52. Which type of plant signaling molecule is similar in structure to aspirin?
a.
abscisic acid
b.
ethylene
c.
salicylic acid
d.
jasmonate
e.
oligosaccharin
53. The first peptide hormone discovered in plants was ____, which functions in wound response in the
tomato.
a.
cytokinin
b.
systemin
c.
gibberellin
d.
jasmonate
e.
salicylic acid
54. The synthesis of ____ is triggered when cells bind systemin.
a.
gibberellin
b.
auxin
c.
jasmonate
d.
cytokinin
e.
brassinosteroids
55. When a plant has a hypersensitive response, production of ____ triggers effects such as the expression
of PR proteins.
a.
oligosaccharins
b.
salicylic acid
c.
ethylene
d.
cytokinin
e.
brassinosteroids
56. Chitinases are examples of
a.
systemins.
b.
phytoalexins.
c.
PR proteins.
d.
R genes.
e.
heat-shock proteins.
57. Secondary metabolites that function to protect plants from viral, fungal and bacterial pathogens are
a.
systemins.
b.
phytoalexins.
c.
PR proteins.
d.
R genes.
e.
heat-shock proteins.
58. Secondary metabolites are termed “secondary” because
a.
they are synthesized as part of basic metabolism.
b.
they are only synthesized in plant leaves.
c.
they are synthesized as precursors to primary metabolism.
d.
they are not synthesized in all plant cells as part of basic metabolism.
e.
they are only synthesized in plant roots.
59. After a plant has survived a microbial invasion, the rest of the plant is often less vulnerable to future
infections. This is called
a.
systemic acquired resistance.
b.
wound defense.
c.
gene-for-gene recognition.
d.
hypersensitive response.
e.
jasmonate response.
60. In systemic acquired resistance, the regulatory protein NPR-1 moves from the cytoplasm to the cell
nucleus, apparently in response to a buildup of ____ in the cytoplasm.
a.
ethylene
b.
brassinosteroids
c.
oligosaccharins
d.
jasmonates
e.
salicylic acid
61. Chaperone-type proteins that stabilize other proteins in response to environmental stresses such as
salinity, drought, heat, and cold are
a.
systemins.
b.
phytoalexins.
c.
PR proteins.
d.
R genes.
e.
heat-shock proteins.
62. The main stimulus for phototropism is light of ____ wavelengths.
a.
red
b.
green
c.
yellow
d.
blue
e.
far red
63. Statoliths, particles that move in the direction gravity pulls them, are typically ____ in plants.
a.
amyloplasts
b.
calcium carbonate crystals
c.
nuclei
d.
vacuoles
e.
hormones
64. Which type of plant hormone appears to play a major role in gravitropism in roots and shoots?
a.
salicylic acid
b.
gibberellins
c.
abscisic acid
d.
auxins
e.
oligosaccharins
65. Thigmotropism is a growth response to
a.
light.
b.
day length.
c.
contact with a solid object.
d.
circadian rhythms.
e.
gravity.
66. You observe a sunflower that moves its leaves so that it tracks the sun across the sky through the day,
and a sensitive plant that reversibly folds up its leaflets when you touch it. These are both examples of
a.
phototropism.
b.
thigmotropism.
c.
stress responses.
d.
circadian rhythms.
e.
nastic movements.
67. Plant activities that follow a biological clock so that they are based on cycles of about 24 hours are
a.
gravitropisms.
b.
photoperiodisms.
c.
thigmotropisms.
d.
circadian rhythms.
e.
phototropisms.
68. Plant responses to the relative lengths of light and dark periods in their environment during each 24-
hour period are
a.
gravitropisms.
b.
photoperiodisms.
c.
thigmotropisms.
d.
circadian rhythms.
e.
phototropisms.
69. Which of the following serves as a switching mechanism in the photoperiodic response in plants?
a.
phytochrome
b.
auxin
c.
cryptochrome
d.
calmodulin
e.
phytoalexin
70. During daylight hours, primarily
a.
Pr absorbs red light and is converted to Pfr.
b.
Pr absorbs far-red light and is converted to Pfr.
c.
Pfr absorbs red light and is converted to Pr.
d.
Pfr absorbs far-red light and is converted to Pr.
e.
Pfr is converted to Pr.
71. At night, assuming no artificial lights, primarily
a.
Pr absorbs red light and is converted to Pfr.
b.
Pr absorbs far-red light and is converted to Pfr.
c.
Pfr absorbs red light and is converted to Pr.
d.
Pfr absorbs far-red light and is converted to Pr.
e.
Pfr is converted to Pr.
72. Chrysanthemums are short-day plants, requiring a night length of longer than 12 hours to flower.
Under which of the following conditions should chrysanthemums flower?
1:
Night length 14 hours, day length 10 hours
2:
Night length 10 hours, day length 14 hours
3:
Night length 14 hours, day length 10 hours; night interrupted in the middle by an intense
red flash
4:
Night length 10 hours, day length 14 hours; day interrupted in the middle by half an hour
of darkness
a.
only 1
b.
only 2
c.
both 1 and 3
d.
both 2 and 4
e.
2, 3, and 4
73. Bearded irises are long-day plants, requiring a night length of less than 12 hours to flower. Under
which of the following conditions should bearded irises flower?
1:
Night length 14 hours, day length 10 hours
2:
Night length 10 hours, day length 14 hours
3:
Night length 14 hours, day length 10 hours; night interrupted in the middle by an intense
red flash
4:
Night length 10 hours, day length 14 hours; day interrupted in the middle by half an hour
of darkness
a.
only 1
b.
only 2
c.
both 1 and 3
d.
both 2 and 4
e.
2, 3, and 4
74. The exposure of plants to low temperatures in order to stimulate flowering is called
a.
cryptotropism.
b.
thigmotropism.
c.
vernalization.
d.
florigen.
e.
cryotropism.
75. Which of the following would probably NOT promote dormancy in at least some plants?
a.
dry soil
b.
nitrogen deficiency
c.
long nights
d.
cold nights
e.
warm nights
76. Flowering in Arabidopsis appears to require
a.
production in leaves of CO protein and FT protein.
b.
movement of CO protein from leaves to the shoot apex.
c.
expression of CO protein in the shoot apex.
d.
movement of FT mRNA from leaves to the shoot apex.
e.
movement of FT protein from leaves to the shoot apex.
77. Research by Christopher Cullis has shown that
a.
the genome size of plants varies little between species.
b.
the genome size of individual plants of the same species is constant.
c.
a plant’s environment can act as a selective agent to establish advantageous variants, but
these variants cannot be transmitted to the next generation.
d.
a plant’s environment can act as a selective agent to establish advantageous variants, and
these variants can be transmitted to the next generation.
e.
the genome size of plants is related to plant size.
MATCHING
Choice
Choose the type of plant hormone most closely associated with the action(s) or researcher(s) given
below.
a.
gibberellins
b.
salicylic acid
c.
auxins
d.
abscisic acid
e.
ethylene
78. Nam-Hai Chua
79. apical dominance
80. fruit ripening
81. bolting
82. Charles and Francis Darwin
83. systemic acquired resistance
84. breaking seed dormancy
752
85. promoting leaf abscission
86. promoting cell division
87. phototropism
88. leaf bud dormancy
89. Frits Went
SHORT ANSWER
90. Describe the various effects of auxins in plants.
91. Explain the hypersensitive response.
92. How might a plant communicate to another plant that it has been attacked by a herbivore?
93. If you were to start growing roses commercially, where would you probably want to set up your
business?
MODIFIED TRUE/FALSE
If the statement is true, answer “T“. If the statement is false, answer “F” and make it correct by
changing the underlined word(s) and writing the correct word(s) in the answer blank(s).
94. Larrea tridenta is chemically defended against most herbivores and some are able to survive
thousands of years.
95. A plant hormone has the same effects in different plant tissues.
96. Specific cells in developing seeds and maturing fruits have receptors for ethylene, but cells in stems
generally do not.
97. Some signaling chemicals, such at oligosaccharins, are only synthesized when a tissue is damaged.
98. Charles Darwin was the first person to discover the hormone auxin.
99. Plant cell walls grow faster in a neutral environment – that is, when the pH is close to 7.
100. External cues such as increasing day length or warming after a cold snap stimulate gibberellin
synthesis, which results in bolting in plants such as cabbages.
101. When a plant becomes infected by pathogenic bacteria or fungi, it may respond by way of a fight or
flight response – a defense that cordons off an infection site surrounding it with dead cells.
102. Tropisms explain how plants can move from place to place.
103. The most widely accepted hypothesis for how plants detect gravity posits that plants detect gravity the
same why animals detect gravity.