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試題題型【閱讀理解 Section A】

試題內容

You do not usually get something for nothing. Now, a new study reveals that the evolution of an improved learning ability could come at a particularly high price: an earlier death.
Past experiments have demonstrated that it is relatively easy .through selective breeding to make rats, honey bees and-that great favourite of researchers-fruit flies a lot better at learning. Animals that are better learners should be competitive and, thus, over time, come to dominate a population by natural selection. But improved learning ability does not get selected amongst these animals in the wilD.No one really understands why.
Tadeusz Kawecki and his colleagues at the University of Fribourg in Switzerland have measured the effects of improved learning on the lives of fruit flies. The flies were given two different fruits as egg-laying sites. One of these was laced with a bitter additive that could be detected only on contact. The flies were then given the same fruit but without an additive. Flies that avoided the fruit which had been bitter were deemed to have learned from their experience. Their children were reared and the experiment was run again.
After repeating the experiment for 30 generations, the children of the learned flies were com- pared with normal flies. The researchers report in a forthcoming edition of Evolution that although learning ability could be bred into a population of fruit flies, it shortened their lives by 15%. When the researchers compared their learned flies to colonies selectively bred to live long lives, they found even greater differences. Whereas learned flies had reduced their life spans, the long-lived flies learned less well than even average flies.
The authors suggest that evolving an improved learning ability may require a greater investment in the nervous system which takes resources away from processes that delay ageing. However, Dr. Kawecki thinks the effect could also be a by-product of greater brain activity increasing the production of Reactive Oxygen Species (ROS), which can increase oxidation in the body and damage health.
No one knows whether the phenomenon holds true for other animals. So, biologists, at least, still have a lot to learn.

1.[單選題]Past experiments prove selective breeding can make animals better_______

A.Commanders
B.Competitors
C.survivors
D.learners

解題思路：細節題。從文章第二段第一句“Past experiments have demonstrated that it is relatively easy through selective breeding to make rats．honey bees and—that great favourite of researchers-fruit flies a lot better at learning．”可知，實驗證明選擇性繁殖可以提高動物的學習能力，故選D。

2.[單選題]In this experiment, scientists observed that________

A.some flies avoided the fruit without an addictive
B.some flies preferred the fruit with an addictive
C.the eggs of the flies were not damaged
D.the impact on the flies did not last long

解題思路：推斷題。從文章第三段第五句“Flies that avoided the fruit which had been bitter were deemed to have learned from their experience．”可知，那些果蠅通過學習能力的提升能夠避開帶有添加劑的水果，由此可以推斷，果蠅已經有經驗，看見同種水果也會避開，所以果蠅也會避開沒有添加劑的同種水果，故選A。

3.[單選題]According to Dr.Kawecki, greater brain activity______

A.reduces oxygen consumption
B.regulates the nervous system
C.speeds up the ageing process
D.stabilizes the ageing process

解題思路：推斷題。從文章第五段最后一句“However，Dr．Kawecki thinks the effect could also be a by—product of greater brain activity increasing the production of Reactive Oxygen Species(ROS)，which Call increase oxidation in the body and damage health．”可知，奎克教授認為這種影響也可能是大腦活動產生活性氧的副作用，活性氧會增強身體的氧化并損害健康。由此可推斷，大量的腦力活動會加速衰老，故選C。

4.[單選題]The forthcoming report says that_______

A.long-lived flies are better at laying eggs
B.long-lived flies are poorer in learning
C.learned flies have a relatively long life
D.learned flies live as long as average ones

解題思路：細節題。從文章第四段最后一句“Whereas learned flies had reduced their life spans，the long—lived flies learned less well than even average flies．”可知，長命果蠅的學習能力低于普通果蠅，故選B。

5.[單選題]We learn from the text that_______

A.the research findings need to be tested further
B.biologists are doing similar research on other animals
C.the animal world usually follows the same universal laws
D.biologists are applying their findings to other areas

解題思路：推斷題。從文章最后一段“N0 0ne knows whether the phenomenon holds true for other animals．So，biologists，at least，still have a lot to learn．”可知，生物學家們目前只對果蠅做了實驗，還不知道其他動物是否有同樣效果，他們還要去繼續研究，故選A。

參考答案：D,A,C,B,A

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