Question

There are new findings that not enough sleep may cause people to gain weight. Researchers say a lack of sleep can produce hormonal(激素的) changes that increase feelings of hunger.

In one study, researchers in the United States examined information on more than 1000 people. The people had taken part in a long-term study of sleep disorders.

Some people slept less than five hours a night. They had 15 percent higher blood levels of a hormone called ghrelin than people who slept eight hours. And they had 15 percent less of the hormone leptin. Experts say ghrelin helps make people feel hungry; leptin makes you feel full.

The scientists say these hormonal changes may be a cause of obesity in Western societies. They note the combination that sleep limitation is common and food is widely available.

The results were not affected by how much people exercised. People who are awake longer have more time to burn energy. But the researchers say loss of sleep may increase hunger especially for high-calorie foods, so people gain weight. It seems that, for survival, the body may be designed to store more fat during times with less sleep.

Researchers from Stanford University in California and the University of Wisconsin did the study. They found that the best amount of sleep for weight control is 7.7 hours a night.The Public Library of Science published the findings in its journal Medicine . Internet users can read the full study, free of charge, at plos. org.

1.Not enough sleep can cause obesity by ______.

A. burning more of your energy

B. making you want to eat more food

C. keeping you from doing exercise

D. helping you feel great without food

2.When you sleep 7.7 hours a night, you will ______ .

A. have your ghrelin level rise and leptin level drop

B.have your leptin level rise and ghrelin level drop

C.have your ghretin and leptin levels properly balanced

D.have your hunger increase and your weight decrease

3.You can read the findings________

A. Only on the Internet

B. only in Medicine

C. Both on the Internet and in Medicine

D. Neither on the Internet nor in Medicine

Answer

1.B

2.C

3.C

【解析】

试题分析：本文介绍了一个新的科学发现，即睡眠不足会导致人体肥胖。研究表明在缺少睡眠的情况下，人体会产生一种叫做ghrelin的激素，会使人产生饥饿感，因而食欲旺盛继而导致肥胖，而且锻炼对于这种因睡眠不足造成的肥胖没有影响。

1.B细节理解题。从文章倒数第二段 the researchers say loss of sleep may increase hunger especially for high-calorie foods, so people gain weight.得知睡眠不足会造成饥饿感，使人们想吃更多高热量的食物，因此导致肥胖，所以B选项正确。

2.C推理判断题。从文章第二段可知缺少睡眠人体会产生让人感到饥饿的ghrelin，而 睡眠充足的话人体会产生让人有饱腹感的 leptin，而且从文章最后一段They found that the best amount of sleep for weight control is 7.7 hours a night可知睡眠7.7小时是能控制体重的最佳时间，也就是在7.7小时内人体产生的ghretin 和 leptin保持平衡。所以C选项正确。

3.C 细节理解题。从文章末句The Public Library of Science published the findings in its journal Medicine . Internet users can read the full study, free of charge, at plos. org.可知研究结果在杂志和网上都可以看到。所以C选项正确。

考点：考查科普知识类短文阅读。