mayank1104
Explanation for Q3 please. Thanks in advance!
1.
The word "suggests" in the question indicates that this is an inference question. The
correct answer, therefore, will not be directly stated in the passage, but it will be
based only on information found within the passage, with no outside speculation or
assumptions necessary.
(A) Paragraph 2 states that COX-1 enzymes stimulate production of prostaglandins
that "protect the stomach from irritating gastric acids.” As stated in paragraph 3,
however, COX-2 inhibitors were designed to affect only COX-2; the specific impetus
was not to interrupt the beneficial effects of COX-1.
(B) The author never describes the side effects caused by COX-2 and furthermore
he states in paragraph 3 that the COX-2 drugs were designed “in order to eliminate
the side effects of aspirin and related drugs.” Paragraph 2 states that Naproxen is
one of those related drug.
(C) CORRECT. Paragraph 3 states that the drug class known as COX-2 inhibitors
was introduced by “several pharmaceutical companies in the 1990s." Paragraph 1
states “their mechanisms of action having been discovered only in 1971." This
suggests that approximately 20 years passed between the initial discovery and the
introduction of COX-2 inhibitors.
(D) This choice is incorrect as it describes COX-2 enzymes, not COX-2 inhibitors; in
addition, the information is directly stated in the passage rather than suggested.
Paragraph 2 states that COX-2 appears to stimulate production of prostaglandins
that "induce inflammation in injured tissues.”
(E) This choice is incorrect as it describes prostaglandins, not the drug class COX-2
inhibitors. Paragraph 2 states that prostaglandins are "generated by most
mammalian tissues in response to external stimuli" and "prostaglandins act on the
cells that produce them."
2.
The "True/False" technique is useful for EXCEPT questions. Four of the answer
choices will contain information found in the passage; these will be labeled True.
One answer choice will contain information not found in the passage; it will be
labeled False.
(A) True. Paragraph 2 states “prostaglandins were first discovered in the 1930s."
(B) True. Paragraph 2 states prostaglandins are "generated by most mammalian
tissues.”
(C) True. Paragraph 1 states that prostaglandins are "responsible for producing the
sensation of pain in the human body, among other functions.”
(D) CORRECT. False. The author never claims that prostaglandins cause side
effects. According to paragraph 4, the COX inhibitor drugs, not prostaglandins,
caused side effects that went undetected during clinical trials.
(E) True. Paragraph 2 states that “aspirin alleviates pain by inhibiting... COX; this
inhibition prevents the production of prostaglandins" and goes on to list the three
forms of the enzyme, COX-1, COX-2, and COX-3.
3.
If prostaglandins are a response to external stimuli, or stimuli outside of the body,
then that external stimuli must be closely linked to at least one of the major functions
of prostaglandin.
(A) Stomach ulcers are produced or aggravated by aspirin and similar drugs, not
prostaglandins (and, in fact, these drugs inhibit prostaglandins).
(B) It is mentioned in the passage that “prostaglandins act on the cells that produce
them,” but the author does not draw a connection between where prostaglandins act
and what (i.e. external stimuli) generates their production.
(C) Paragraph 2 states that aspirin, not prostaglandin, prevents cyclooxygenase from
functioning.
(D) Paragraph 2 states that most mammalian hormones "are synthesized in one
tissue but act on a distant one" and contrasts prostaglandins, which "act on the cells
that produce them" or on other nearby cells. This difference is based upon where
the hormones act, not on what the hormones are responding to (whether external
stimuli or something else).
(E) CORRECT. Paragraph 1 states that prostaglandins are "responsible for
producing the sensation of pain in the human body, among other functions.” In the
second paragraph the author mentions that aspirin alleviates pain by preventing the
production of prostaglandins. To bridge the two assertions, the author provides
evidence that prostaglandins are indeed responsible for the sensation of pain, an
external stimuli.
4.
The first paragraph introduces COX-2 inhibitors and talks briefly about a 1971
discovery linking aspirin to prostaglandins. Paragraph 2 elaborates on the
connections among aspirin, prostaglandins, and the three types of COX enzymes.
Paragraph 3 discusses COX-2 inhibitors specifically, both the impetus for creating
them and some negative effects. The final paragraph provides caution about the
promise of COX-2 inhibitors.
(A) The passage explains the intended benefits behind the development of COX-2
inhibitors, but this is much too narrow to be the main purpose of the passage,
particularly when a large part of the passage addresses the negative consequences.
(B) The author does not initiate a “debate.” For a debate, the author must introduce
two clear opposing sides. The COX-2 inhibitors were developed to replace the earlier
drugs that inhibited both COX-1 and COX-2, but then they were also found to have
side effects.
(C) While paragraph 4 states that “Side effects almost always cropped up, even after
clinical trials that seemed to indicate none," the author notes this only in the context
of explaining the result of COX-2 inhibitors. This is too narrow to be the main
purpose of the passage.
(D) CORRECT. This choice reflects the summary above: why COX-2 inhibitors were
developed and the result of the drugs' introduction into the marketplace.
(E) This is incorrect because the passage never mentions a drug class of “COX-1
inhibitors.” COX-1 is introduced as an enzyme; it is not a class of drug.