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练习题-2(附答案)(5)
文章出处:  发布时间:2006-07-09

7.Australians appear to have responded to the call by a former Prime Minister to become better qualified.
8.Australia s education system is equal to any in the world in the opinion of most educationists.

Reading Passage 1 below.
Right and left-handedness in humans
  Why do humans, virtually alone among all animal species, display a distinct
left or right handedness? Not even our closest relatives among the apes possess
such decided lateral asymmetry, as psychologists call it. Yet about 90 per
cent of every human population that has ever lived appears to have been
right-handed. Professor Bryan Turner at Deakin University has studied the
research literature on left-handedness and found that handedness goes with
sidedness. So nine out of ten people are right-handed and eight are
right-footed. He noted that this distinctive asymmetry in the human population
is itself systematic. `Humans think in categories: black and white, up and
down, left and right. It s a system of signs that enables us to categorise
phenomena that are essentially ambiguous.
  Research has shown that there is genetic or inherited element to handedness.
But while left-handedness tends to run in families, neither left nor right
handers will automatically produce off-spring with the same handedness; in
fact about 6 per cent of children with two right-handed parents will be
left-handed. However, among two left-handed parents, perhaps 40 per cent of
the children will also be left-handed. With one right and one left-handed
parent, 15 to 20 per cent of the offspring will be lefthanded. Even among
identical twins who have exactly the same genes, one in six pairs will differ
in their handedness.
  What then makes people left-handed if it is not simply genetic? Other factors
must be at work and researchers have turned to the brain for clues. In the
1860s the French surgeon and anthropologist, Dr Paul Broca, made the
remarkable finding that patients who had lost their powers of speech as a
result of a stroke (a blood clot in the brain) had paralysis of the right half
of their body. He noted that since the left hemisphere of the brain controls
the right half of the body, and vice versa, the brain damage must have been
in the brain s left hemisphere, Psychologists now believe that among right
handed people, probably 95 per cent have their language centre in the left
hemisphere, while 5 per cent have right-sided language, Left-handers, however,
do not show the reverse pattern but instead a majority also Some 30 per cent
have right hemisphere language.
  Dr Brinkman, a brain researcher at the Australian National University in
Canberra, has suggested that evolution of speech went with right-handed
preference. According to Brinkman, as the brain evolved, one side became
specialised for fine control of movement (necessary for producing speech) and
along with this evolution came righthand preference. According to Brinkman,
most left-handers have left hemisphere dominance but also some capacity in
the right hemisphere. She has observed that if a left-handed person is
brain-damaged in the left hemisphere, the recovery of speech is quite often
better and this is explained by the fact that left-handers have a more
bilateral speech function.In her studies of macaque monkeys, Brinkman has
noticed that primates (monkeys) seem to learn a hand preference from their
mother in the first year of life but this could be one hand or the other. In
humans, however, the specialisation in function of the two hemispheres results
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