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SECTION 4
Directions: Each question below consists of a word printed in capital letters followed by five lettered words or phrases. Choose the lettered word or phrase that is most nearly opposite in meaning to the word in capital letters. Since some of the questions require you to distinguish fine shades of meaning, be sure to consider all the choices before deciding which one is best.
ABEYANCE:
One reason why a sheep, a less well-understood experimental subject than
the laboratory mouse, should have proved easier to clone may stem from
differences in the initial stages of the two species' embryonic development.
After reaching maturity in the ovary of the mother, the unfertilized eggs of all
(5) mammals accumulate a supply of proteins, and the means of producing fresh
protein. In this way, the mammalian egg brings with it a larder for the embryo
to make use of until its own genes activate and supply this requirement
themselves. The sheep embryo disposes of its store properly and need not
depend on its own genes until the sixteen-cell stage, four cell divisions
(10) successive to fertilization, while in contrast, the mouse embryo commences this
process more precociously, becoming reliant on the activity of its own genes
after just the first division when the fertilized egg becomes two cells.
Therefore, a foreign nucleus introduced into a sheep egg exploits a respite in its
host's biological development, allowing it to adapt to its new role before
(15) assuming genetic control.
Concomitantly, a nucleus introduced into a mouse egg must acclimatize
quickly for its genes to be able to direct embryonic development within a single
cell division, so perhaps there is insufficient time for the extensive re-
programming of compulsory gene activity. The human embryo is thought to rely
(20) on its own genes after three cellular divisions, which might or might not
provide time enough for a foreign nucleus to acclimate. However, were
scientists to comprehend the nature of the indispensable re-programming then
there is every likelihood that both mice and humans could be cloned.
Despite the long-standing availability of this technology, there has until
(25) recently been little interest in it. Some people suffering from infertility as a
result of rare hereditary diseases could produce offspring, but cloned individuals
may be at risk given scientists' limited knowledge of the long term effects of
allowing an "old" adult cell nucleus to commence life again in an egg. The
nucleus of a skin cell could have accumulated a multitude of genetic mistakes of
(30) no consequence to its role in the skin, but the same cell could prove deleterious
in other tissues, or immensely increase the probability of the affliction with
cancer. The threat to general human health posed by cloning, as opposed to the
individual, is difficult to determine, but the risks are almost certainly lower
than those encountered in the effective inbreeding of consanguine marriages,
(35) and thus there are no scientific grounds per se for banning cloning. Like other
practices inconsequential to the physical well being of humanity, but generally
deemed undesirable on moral or social grounds, the prohibition of human
cloning will ultimately rest with only a simple pragmatic decision.
In this passage, the author is primarily concerned with
It can be inferred that a rat with its infralimbic cortices destroyed would respond which
As the political consequences of Nazism and the liberal tone of the postwar
world proved inhospitable to Darwinist thinking, so the disintegration of the
postwar order, the end of traditional leftwing politics, a growing social
conservatism and disillusionment with the idea of social progress has led to its
(5) return. As anthropologist Foley expounded, the history of the twentieth
century has transformed our vision of humanity, leading to a loss of confidence
in the notion that humans may be raised on a taxonomical pedestal above the
swamp of animal brutishness. In deriding any social explanation of human
behavior, and implying that emotions are biologically shaped, hence universal,
(10) scientists have come to odds with cultural anthropologists, who ridicule any
biological interpretation of human behavior. and view humans in strictly cultural
terms.
There is convincing evidence that the anthropologists are correct, for even
something as fundamental as an emotion is far more than simply an evolutionary
(15) trait, given that only some emotions--anger, disgust, sadness, enjoyment and
fear--are known to be universal, while others, such as jealousy and envy, vary
in their expression and are arguably not emotions at all. Even emotions known
to be universal cannot be regarded as simply "natural", given that the evocation
of a particular emotion is both culturally and historically specific. The
(20) connotation of anger or sadness and the elicitors of these emotions may vary
across cultures and throughout human history. There are also culturally bound
"display rules", often unconscious, which dictate the means or time of
displaying emotion. For instance, Japanese and American students are privately
shown very similar emotions in response to similar stimuli, but their public
(25) expressions are far from identical, a fact that may owe to the Japanese cultural
tendency of remaining demure in public expression.
Even more contentious is the question of what emotions animals possess, of
whether they are aware of such emotions, and of the relationship between
animal responses and human emotions. The way of responding to these debates
(30) depends as much upon one's philosophical inclinations as on the facts: scientists
philosophically disposed to minimize the gap between humans and animals are
more likely to perceive animals as having emotions, as being aware of them,
while those anthropologists who seek an unbridgeable gap between humanity
and lower life forms are likely to see appreciable differences between human
(35) emotions and animal responses. Thus, the scientific idea of the human is not simply an
objective truth, but shaped by wider issues such as the prevailing ideas of progress,
notions of racial difference, and the comprehension of the relationship between Man and
Nature. All that may safely be concluded is that what constitutes a human is not only
innate, but also nurtured.
The author of the passage is primarily concerned with
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