Question

Research suggests that a newly-identified gene known as insomniacs(失眠癥患者) may play a role in keeping us asleep. By cloning and testing this gene in about 21,000 fruit flies, Rockefeller University researchers say they have discovered an entirely new mechanism (機(jī)制) by which sleep is controlled.
By studying these flies, the researchers discovered that mutations(變異) in the insomniac gene were associated with a great reduction in sleep. While a typical fruit fly slept for an average of 927 minutes a day, the mutant flies slept for just 317. They also slept for shorter periods of time, and slept and woke more frequently.
“The results showed a great loss of both the time that the flies’ sleep lasted and their ability to remain asleep after they slept,” says researcher Nicholas Stavropoulos.
The researchers also examined the link between sleep and lifespan, finding that flies with mutations to the insomniac gene lived only about two-thirds as long as unchanged flies. But when the scientists removed insomniac only in neurons（神經(jīng)細(xì)胞）---allowing it to remain in the rest of the flies’ bodies---this difference disappeared; the resulting animals slept poorly but lived just as long.
“This suggests that reduced sleep can be ‘uncoupled’(分開) from reduced lifespan, supporting the idea that some interruptions of sleep do not affect overall health, at least as far as lifespan is concerned,” Stavropoulos says.
Although flies and humans would appear to have little in common when it comes to lifestyle, scientists say that the mechanisms of sleep and wakefulness are likely to be quite similar.
“Sleep is a fundamental behavior in all animals, and it is poorly understood from a scientific standpoint, says Stavropoulos. This work could prove useful in understanding and treating sleep disorders”

1. 1.
   The text is mainly about____
   1. A.
      the progress in cloning fruit flies
   2. B.
      the methods of cloning fruit flies
   3. C.
      the link between gene and lifespan
   4. D.
      the influence of a gene on the ability to sleep
2. 2.
   According to paragraph2, the mutant flies________
   1. A.
      slept about 5 hours a day
   2. B.
      had problems waking up
   3. C.
      didn’t seem sleepy at all
   4. D.
      could not fall asleep
3. 3.
   We can conclude from the text that________
   1. A.
      sleep and health go hand in hand
   2. B.
      sleep can be controlled by humans
   3. C.
      research into sleep is very fruitful
   4. D.
      the findings are useful in medical treatment

Answer 1

DAD
試題分析：本文敘述了通過對(duì)果蠅的科學(xué)研究發(fā)現(xiàn)基因影響睡眠的能力，而一般情況下果蠅睡眠平均每天927分鐘,變異果蠅睡了只有317分鐘，他們睡眠的時(shí)間更短了,睡著了,醒來時(shí)卻更頻繁。蒼蠅和人類在生活方式上似乎沒有什么共同點(diǎn),但是睡眠和清醒的情況也可能非常相似。這個(gè)研究發(fā)現(xiàn)可能對(duì)于治療睡眠障礙有一定的幫助。
1.主旨大意題。根據(jù)By studying these flies, the researchers discovered that mutations(變異) in the insomniac gene were associated with a great reduction in sleep.可知基因影響睡眠的能力，故選D。
2.細(xì)節(jié)理解題。根據(jù)the mutant flies slept for just 317，變異果蠅一天睡眠的時(shí)間大約5個(gè)小時(shí)，故選A。
3.推理判斷題。根據(jù)This work could prove useful in understanding and treating sleep disorders，可知這個(gè)發(fā)現(xiàn)可能在醫(yī)學(xué)治療方面有用，故選D。
考點(diǎn)：考查科普類短文閱讀。