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kel2010
- Junior | Next Rank: 30 Posts
- Posts: 16
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In an example reported by Bryant, plants
appear to have developed a phytochemical
defense against the depredations of snowshoe
hares in Canada. Every ten years, for reasons
that are unclear, the hare population swells. The
result is overbrowsing of certain deciduous trees
and shrubs. Bryant found that trees favored by
the hare produce young shoots high in terpene
and phenolic resins, which discourage hare
browsing. After treating non-resinous willow twigs
with resinous extracts and placing treated and
untreated samples at hare feeding stations,
Bryant found that samples containing at least
half of the resin concentration of natural twigs
were untouched. The avoidance of resinous
shoots, he concludes, may play a role in the
decline of the hare population to normal levels.
Which of the following statements can be
inferred about plant shoots containing large
amounts of terpene and phenolic resins?
I. They serve as a form of natural defense.
II. Their growth is stimulated by increases in
the hare population.
III. They are unappetizing to hares.
(A) I only
(B) II only
(C) III only
(D) I and III only
(E) I, II, and III
its ans is D. can anyone expain to me why II is incorrect? according to me II is also supported by the passage.
i have taken this from Kaplan RC.
appear to have developed a phytochemical
defense against the depredations of snowshoe
hares in Canada. Every ten years, for reasons
that are unclear, the hare population swells. The
result is overbrowsing of certain deciduous trees
and shrubs. Bryant found that trees favored by
the hare produce young shoots high in terpene
and phenolic resins, which discourage hare
browsing. After treating non-resinous willow twigs
with resinous extracts and placing treated and
untreated samples at hare feeding stations,
Bryant found that samples containing at least
half of the resin concentration of natural twigs
were untouched. The avoidance of resinous
shoots, he concludes, may play a role in the
decline of the hare population to normal levels.
Which of the following statements can be
inferred about plant shoots containing large
amounts of terpene and phenolic resins?
I. They serve as a form of natural defense.
II. Their growth is stimulated by increases in
the hare population.
III. They are unappetizing to hares.
(A) I only
(B) II only
(C) III only
(D) I and III only
(E) I, II, and III
its ans is D. can anyone expain to me why II is incorrect? according to me II is also supported by the passage.
i have taken this from Kaplan RC.
