考研英语笔记——2005年真题

Section I Use of English

1.

The human nose is an underrated tool. Human are often thought to be insensitive smellers compared with animals, 1.but this is largely because, 2.unlike animals, we stand upright. This means that our noses are 3.limited to perceiving those smells which float through the air, 4.missing the majority of smells which stick to surfaces. In fact 5.though, we are extremely sensitive to smells, 6.even if we do not generally realize it. Our noses are capable of 7.detecting human smellls even when these are 8.diluted to far below one part in one million.

词汇突破：
1. underrate [ʌndə’reɪt] 低估；看轻
2. insensitive
3. smeller
4. stand upright
5. perceive [pə’siːv] 察觉，感觉；理解；认知
6. stick to
7. capable
8. detect vt.察觉；发现；探测
distingguish|discover|determine|
9. dilute [daɪ’l(j)uːt; dɪ-] 稀释（的）；冲淡
dissol溶解 | disperse [dɪ'spɜːs]分散，散开 | diffuse传播；（气体、热量等）扩散
10. part [僻义] n.（度量单位的）等份

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2.

Strangely, some people find that they can smell one type of flower but not another, 9.whereas others are sensitive to the smells of both flowers. This may be because some people do not have the genes necessary to generate 10.particular smell receptors in the nose. These receptors are the cells which sense smells and send 11.messages to the brain. However, it has been found that even people insensitive to a certain smell 12.at first can suddenly become sensitive to it when 13.exposed to it often enough.

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3.

The explanation for insensitivity to smell seems to be that the brain finds it 14.inefficient to keep all smell receptors working all the time but can 15.create new receptors if necessary. This may 16.also explain why we are not usually sensitive to our smells—we simply do not need to be. We are not 17.aware of the usual smell of our own house, but we 18.notice new smells when we visit someone else’s. The brain finds it best to keep smell receptors 19.available for unfamilar and emergency signals 20.such as the smell of smoke, which might indicate the danger of fire.