How much sleep does a person need？【31】the physiological bases of the need for sleep remain

of how much sleep we ought to have. There are some who think we can leave the body to regulate these matters for itself. "The answer is easy," says Dr. A. Burton. "With the tight amount of sleep you should wake up fresh and alert five minutes before the alarm tings." If he is right many people must be under sleeping, including myself. But we must remember that some people have a greater inertia than others. This is not meant rudely. They switch on Slowly, and they are reluctant to switch off. They are alert at bedtime and sleepy when it is time to get up, and this may have nothing to do with how fatigued their bodies are, or how much sleep they must take to lose their fatigue.

Other people feel sure that the present trend is towards too little sleep. To quote one medical opinion, "Thousands of people drift through life suffering from the effects of too little sleep; the reason is not that they can't sleep. Like advancing colonists, we do seem to be grasping ever more of the land of sleep for our waking needs, pushing the boundary back and reaching, apparently, for a point in our evolution where we will sleep no more. This in itself, of course, need not be a bad thing. What could be disastrous, however, is that we should press too quickly towards this goal, sacrificing sleep only to gain more time in which to jeopardize our civilization by actions and decisions made weak by fatigue.

Then, to complete the picture, there are those who believe that most people are persuaded to sleep too much. Dr. H. Roberts, writing in Every Man in Health, asserts it may safely be stated also. It would be a pity to retard our development by holding back those people who are gifted enough to work and play well with less than the average amount of sleep, if indeed it does them no harm. If one of the trends of evolution is that more of the life span is to be spent in gainful waking activity, then surely these people are in the van of this advance.

The author seems to indicate that ______.

A．there are many controversial issues like the right amount of sleep

B．among many issues the right amount of sleep is the least controversial

C．people are now moving towards solving many controversial issues

D．the right amount of sleep is a topic of much controversy among doctors

cientists are making experiments on rats to try to determine the efforts of over crowded conditions on man. Recent studies have shown that the behaviour of rats is greatly affected by space. If rats have enough living space, they eat well, sleep well and produce their young well. But if their living conditions become too crowded, their behaviour and even their health change obviously. They can't sleep and eat well, and signs of fear and worry become clear. The more crowded they are, the more they tend to bite each other and even kill each other. Thus, for rats, population and violence are directly related. Is this a natural law for human society as well？ Is enough space not only satisfactory, but necessary for human survival？

The writer is mainly talking about ______.

A．a person's living space needs

B．building and floors

C．equipment and conditions

D．population and violence

adequately met？ Sociologists and psychologists are conducting experiments on rats to try to determine the effect of overcrowded conditions on man. Recent studies have shown that the behavior. of rats is greatly affected by space. If rats have adequate living space, they eat well, sleep well, and reproduce well.

However, if their living conditions become too crowded, their behavior. patterns and even their health perceptibly change. They cannot sleep or eat well, and signs of fear and tension become obvious. The more crowded they are, the more they tend to bite each other and even kill each other. Thus for rats, population and violence are directly related. Is this a natural law for human society as well？ Is adequate space not only desirable, but also essential for human survival？

This passage is mainly about ______.

A.living space and behavior

B.population and living conditions

C.interesting experiments on rats

D.a natural law for human society

What is the purpose of the experiments described in the passage？A.To determine how much living space a rat needs.

B.To see what happens when rats live in a limited space.

C.To know the likely effects of inadequate living space on human beings.

D.To find out the relationship between population and living conditions.

How would rats behave when their living conditions become too crowded？A.They eat a lot and become friendly to others.

B.They sleep little and act quite peacefully.

C.They eat little but sleep soundly.

D.They become nervous and tend to be war-like.

The passage suggests that overcrowded conditions ______.A.are directly related with population

B.may cause an increase in violence

C.may lead to high birth rate

D.may bring about pollution problems

请帮忙给出每个问题的正确答案和分析，谢谢！

（英语类学生必做）

Sleep is important to us because it helps restore organs and tissues in our body. But how much sleep do we actually need？

For most of us, eight hours seems to be about the right amount. Yet we know that there are many people who get 【61】 perfectly with less sleep, and some who may need 【62】 A great deal depends on the 【63】 we live. But a good general rule 【64】 is to sleep as long as we have to in order to feel happy and be able to work 【65】 our best when we awaken.

There are actually different 【66】 of sleep. There is a deep sleep and a shallow sleep. In a shallow sleep our body does not get the same kind of rest it gets in a 【67】 sleep, 【68】 after eight hours of a shallow sleep we may still feel tired. But a short, deep sleep can be very 【69】 Alexander—the Great Emperor was able to get a deep sleep 【70】 he needed it. Once, during the night before an important battle, he remained 【71】 longer than anyone else. 【72】 he wrapped himself in a cloak and 【73】 down on the earth. He slept so 【74】 that his generals had to wake him three times for him to give the 【75】 to attack!

Normally when we go to sleep, our " sleep center" blocks off nerves so that 【76】 our brain and body go to sleep. 【77】 prevents us from wanting to do anything, and the other 【78】 our internal organs and limbs go to sleep. 【79】 sometimes only one goes to sleep and the other does not. A very tired soldier can sometimes 【80】 asleep (brain sleep) and keep on marching, because his body is not asleep.

(86)

A．across

B．away

C．along

D．over

So much ______ his financial position that he can't sleep at night.

A. he worries about

B. he worried about

C. did he worry about

D. does he worry about

rnating with some 16-17 hours' wakefulness and that, broadly s peaking, the sleep normally coincides with the hours of darkness. Our present concern is with how easily and to what extent this cycle can he modified.

The question is no mere academic one. The ease, for example, with which people can change from working in the day to winking at night is a question of growing importance in industry where automation calls for round-the-clock working of machines. It normally takes from five days to one week for a person to adapt to a reversed routine of sleep end wakefulness, sleeping during the day end working at night. Unfortunately, it is often the case in industry that shifts are changed every week; a person may work from 12 midnight to 8 a.m. one week, 8 a.m. to 4 p.m. the next, and 4 p. m. to 12 midnight the third and so on. This means that no sooner bas he got used to one routine than he has to change to another, so that much of his time is spent neither working nor sleeping very efficiently.

The only real solution appears to be to hand over the night shift to a number of permanent night workers. An interesting study of the domestic life and health of night-shift workers was carried out by Brown in 1957. She found a high incidence of disturbed sleep and other disorders among those on alternating day and night shifts, but no abnormal occurrence of these phenomena among those on permanent night work.

This latter system then appears to be the best long-term policy, but meanwhile something may be done to relieve the strains of alternate day and night work by selecting those people who can adapt most quickly to the changes of routine. One way of' knowing when a person has adapted is by measuring his body temperature. People engaged in normal daytime work will have a high temperature during the hours of wakefulness and a low one at night; when they change to night work the pattern will only gradually go back to match the new routine and the speed with which it does so parallels, broadly speaking, the adaptation of the body as a whole, particularly in terms of performance. There from, by taking body temperature at intervals of two hours throughout the period of wakefulness it can be seen how quickly a person can adapt to a reversed routine, and this could be used as a basis for selection. So far, however, such a form. of selection does not seem to have been applied in practice.

Why is the question of "how easily people can get used to working at night？" not a mere academic question？

A．Because few people like to reverse the cycle of sleep aud wakefulness.

B．Because sleep normally coincides with the hours of darkness.

C．Because people are required to work at night in some fields of industry.

D．Because shift work in industry requires people to change their sleeping habits.

s won't notice. A new study published in The Annals of Internal Medicine (a medical journal) finds that inadequate shut-eye has a harmful effect on fat cells, reducing their ability to respond to insulin (胰岛素) by about 30 percent. Over the long-term, this decreased response could set the stage for type-2 diabetes (a medical condition in which someone has too much sugar in his or her blood), fatty liver disease and weight gain.

The study adds to a growing body of evidence that there' “an intimate relationship between the amount of sleep we get and our ability to maintain a good, healthy body weight,” says sleep expert Helene Emsellem, director of the Center for Sleep and Wake Disorders in Chevy Chase, Maryland. But Americans don't seem to be getting the message that we need seven to nine hours par night. More than 1 in 5 of us, according to a report from the Centers for Disease Control and Prevention, is getting six or fewer hours of sleep per night, on average.

So how did researchers study fat cells in the Annals paper？ Matthew Brady of the University of Chicago and a group of colleagues selected and persuaded seven volunteers to take part in the research project. They were all young, thin and healthy and agreed to sleep for eight nights in a sleep lab. “For four nights they were allowed to stay in bed for 8.5 hours a night,” says Brady. Then, a month later, they came back for four additional nights——but this time they were allowed just 4.5 hours of sleep per night. And after each visit, researchers got a sample of their fat. Brady explains that the fat cells responded significantly to the loss of sleep. “I was very surprised to be honest,” he says.

Bad things can happen when fat cells become less responsive to insulin. “Fat cells are actually your friend,” he says. “They're there to store lipids (血脂).” When lipids stay inside the cells, your body can utilize the fat when you're exercising or sleeping or going about your day. “However, when fat cells stare to become insulin resistant, the lipids star to leach out of the fat cells and rise in the bloodstream,” Brady says.

1. According to the passage, lack of sleep for a long while can probably lead to all of the following EXCEPT {A; B; C}.

A. heart disease

B. weight gain

C. diabetes

2. The main idea of the third paragraph is {A; B; C}.

A. how to write a medical research paper

B. how to avoid sleep loss

C. how the research was conducted

3. What does the “leach” in the last paragraph probably mean？{A; B; C}

A. Leap.

B. Lead.

C. Leak.

4. Which of the following is NOT TRUE according to the passage？{A; B; C}

A. We will be in trouble if our fat cells become less responsive to insulin.

B. More and more studies are done to study the link between sleep and weight.

C. More than 20% of Americans are not getting enough sleep.

5. Which of the following is an appropriate title for this passage？{A; B; C}

A. Poor Sleep May Lead to Too Much Stored Fat and Disease

B. Sleep Experts Had Exciting Findings in a Fat Study

C. Americans Should Have More Than Six Hours of Sleep

A.Where is the woman going？

B.What is the main idea of the passage？

C.What’s the man’s house number？

D.How many hours does Tom sleep a day？

How much does it cost() bus？

A.at

B.on

C.by