1. (2022高一下·奉贤期末) 阅读理解

Growing old does not increase your immediate danger of dying — at least, if you are a fruit fly. The chances of a Mediterranean fruit fly dying out on a particular day reaches a peak (顶峰) and then declines, according to James Carey of the University of California and Davis and James Vaupel of Duke University. Their results disagree with the general idea that the death rate rises with age in all species.

The research will cause a long-running debate over whether or not there is a genetically defined limit to an individual's lifespan (寿命). If there is not and the fruit fly results extend to humans, then medical advances might eventually allow the elderly to live forever.

In the early 19th century, the British scientist Benjamin Gompertz formed a law stating that death rates increase with age. For an adult human the immediate chance of death seems to double every eight years. The Gompertz law was believed to hold for all species and to put an age limit on each species.

To test this theory, Carey and Vaupel studied more than a million fruit flies. They found that the death rate reached a maximum of about fifteen per cent when the flies were between 40 and 60 days old, and then fell. Flies that survived to 100 days had only a 4 to 6 per cent chance of dying on a given day. In other words, the chances of dying seem not to increase sharply in advanced age, as predicted by the Gompertz law; rather, they seem to level off.

If Gompertz law does not hold for human beings either, then there may be no genetically defined limit on a person's lifespan.

1. （1） What does the passage mainly deal with?

   A . The habits of fruit flies. B . The possible limit to a person's lifespan. C . The secret of long life. D . The ground for the Gompertz law.
3. （2） The Gompertz law holds that _____.

   A . death rates change every eight years B . the lifespans of different species vary C . most humans die of old age D . a human is more likely to die as he gets older
5. （3） According to the research made on the fruit flies, _____.

   A . the Gompertz law does not hold for human beings B . the death rate does not necessarily increase with age C . the fruit flies will never die after surviving a death rate peak D . nearly half of the fruit flies die at half of their longest lifespan
7. （4） What can be concluded from the passage?

   A . It is difficult to put an age limit on each species. B . There will be far more new species on the earth. C . The death rate of human beings will certainly drop with age. D . People will never suffer from diseases with medical advances.