6.Damaged nerves in the spinal cord do not regenerate themselves naturally, nor even under the spur of nerve-growth stimulants. The reason, recently discovered, is the presence of nerve-growth inhibitors in the spinal cord. Antibodies that deactivate those inhibitors have now been developed. Clearly, then, nerve repair will be a standard medical procedure in the foreseeable future.
Which of the following, if true, casts the most serious doubt on the accuracy of the prediction above?
(A) Prevention of the regeneration of damaged nerves is merely a by-product of the main function in the human body of the substances inhibiting nerve growth.
(B) Certain nerve-growth stimulants have similar chemical structures to those of the antibodies against nerve-growth inhibitors.
(C) Nerves in the brain are similar to nerves in the spinal cord in their inability to regenerate themselves naturally.
(D) Researchers have been able to stimulate the growth of nerves not located in the spinal cord by using only nerve-growth stimulants.(A)
(E) Deactivating the substances inhibiting nerve growth for an extended period would require a steady supply of antibodies.
7.The human body secretes more pain-blocking hormones late at night than during the day. Consequently, surgical patients operated on at night need less anesthesia. Since larger amounts of anesthesia pose greater risks for patients, the risks of surgery could be reduced if operations routinely took place at night.
Which of the following, if true, argues most strongly against the view that surgical risks could be reduced by scheduling operations at night?
(A) Energy costs in hospitals are generally lower at night than they are during the day.
(B) More babies are born between midnight and seven o’clock in the morning than at any other time.
(C) Over the course of a year, people’s biological rhythms shift slightly in response to changes in the amounts of daylight to which the people are exposed.
(D) Nurses and medical technicians are generally paid more per hour when they work during the night than when they work during the day.(E)
(E) Manual dexterity and mental alertness are lower in the late night than they are during the day, even in people accustomed to working at night.
Questions 8-9
Walter: A copy of an artwork should be worth exactly what the original is worth if the two works are visually indistinguishable. After all, if the two works are visually indistinguishable, they have all the same qualities, and if they have all the same qualities, their prices should be equal.
Marissa: How little you understand art! Even if someone could make a perfect copy that is visually indistinguishable from the original, the copy would have a different history and hence not have all the same qualities as the original.
8.Which of the following is a point at issue between Walter and Marissa?
(A) Whether a copy of an artwork could ever be visually indistinguishable from the original
(B) Whether the reproduction of a work of art is ever worth more than the original is worth
(C) Whether a copy of a work of art is ever mistaken for the original
(D) Whether a copy of a work of art could have all the same qualities as the original(D)
(E) Whether originality is the only valuable attribute that a work of art can possess
9.Marissa uses which of the following techniques in attempting to refute Walter’s argument?
(A) Attacking his assumption that the price of an artwork indicates its worth
(B) Raising a point that would undermine one of the claims on which his conclusion is based
(C) Questioning his claim that a perfect copy of a work of art would be visually indistinguishable from the original
(D) Giving reason to believe that Walter is unable to judge the quality of a work of art because of his inadequate understanding of the history of art(B)
(E) Proposing alternative criteria for determining whether two works of art are visually indistinguishable
10.Magnetic resonance imaging (MRI)—a noninvasive diagnostic procedure—can be used to identify blockages in the coronary arteries. In contrast to angiograms—the invasive procedure customarily used—MRI’s pose no risk to patients. Thus, to guarantee patient safety in the attempt to diagnose arterial blockages, MRI’s should replace angiograms in all attempts at diagnosing coronary blockages.
Which of the following, if true, would most support the recommendation above?
(A) Angiograms can be used to diagnose conditions other than blockages in arteries.
(B) MRI’s were designed primarily in order to diagnose blockages in the coronary arteries.
(C) Angiograms reveal more information about the nature of a blockage than an MRI can.
(D) An MRI is just as likely as an angiogram to identify an arterial blockage.(D)
(E) Some patients for whom an angiogram presents no risk are unwilling to undergo an MRI.
11.Naturally occurring chemicals cannot be newly patented once their structures have been published. Before a naturally occurring chemical compound can be used as a drug, however, it must be put through the same rigorous testing program as any synthetic compound, culminating in a published report detailing the chemical’s structure and observed effects.
If the statements above are true, which of the following must also be true on the basis of them?
(A) Any naturally occurring chemical can be reproduced synthetically once its structure is known.
(B) Synthetically produced chemical compounds cannot be patented unless their chemical structures are made public.
(C) If proven no less effective, naturally occurring chemicals are to be preferred to synthetic compounds for use in drugs.
(D) Once a naturally occurring compound has been approved for use as a drug, it can no longer be newly patented.(D)
(E) A naturally occurring chemical cannot be patented unless its effectiveness as a drug has been rigorously established.
12.A public-service advertisement advises that people who have consumed alcohol should not drive until they can do so safely. In a hospital study, however, subjects questioned immediately after they consumed alcohol underestimated the time necessary to regain their driving ability. This result indicates that many people who drink before driving will have difficulty following the advertisement’s advice.
Which of the following, if true, most strongly supports the argument above?
(A) Many people, if they plan to drink alcohol, make arrangements beforehand for a nondrinker to drive them home.
(B) The subjects in the hospital study generally rated their abilities more conservatively than would people drinking alcohol outside a hospital setting.
(C) Some people refrain from drinking if they will have to drive to get home afterward.
(D) The subjects in the hospital study were also questioned about the time necessary to regain abilities that do not play an important role in driving safely.(B)
(E) Awareness of the public-service advertisement is higher among the general population than it was among the subjects in the hospital study.
13. Investigator: XYZ Coins has misled its clients by promoting some coins as “extremely rare” when in fact those coins are relatively common and readily available.
XYZ agent: That is ridiculous. XYZ Coins is one of the largest coin dealers in the world. We authenticate the coins we sell through a nationally recognized firm and operate a licensed coin dealership.
The XYZ agent’s reply is most vulnerable to the criticism that it
(A) exaggerates the investigator’s a claims in order to make them appear absurd
(B) accuses the investigator of bias but presents no evidence to support that accusation
(C) fails to establish that other coin dealers do not also authenticate the coins those dealers sell
(D) lists strengths of XYZ Coins while failing to address the investigator’s charge(D)
(E) provides no definition for the inherently vague phrase “extremely rare”
