The effects of rapid travel on the body are actually far more disturbing than we realize. Jet Lag is not a psychological consequence of having to readjust to a different time zone. It is due to changes in the body’s physiological regulatory mechanisms, specifically the hormonal systems, in a different environment.

     Now that we understand what Jet Lag is, we can go some way to overcome it. A great number of the body’s events are scheduled to occur at a certain time of day. Naturally these have to be regulated, and there are two regulatory systems which interact.

    One timing system comes from the evidence of our senses and stomachs, and the periodicity we experience when living in a particular time zone. The other belongs in our internal clocks (the major one of which may be physically located in a part of the brain called the suprachiasmatic nucleus) which, left alone, would tie the body to a 25-hour rhythm. Normally the two timers are in step, and the surroundings tend to regularize the internal clocks to the more convenient 24-hour period.

     If, however, you move the whole body to a time zone which is four hours different, the two clocks will be out of step, like two alarm clocks which are normally set together, but which have been reset a few hours apart. Whereas the two clocks would normally sound their alarms together, now they ring at different times. Similarly, the body can be set for evening while the sun is rising.

     In time the physiological system will reset itself, but it does take time. One easily monitored rhythm is palm sweating. A man flown to a time zone different by 10 hours will take eight days to readjust his palm sweat. Blood pressure, which is also rhythmical, takes four days to readjust.

What can we do about it? It is not feasible to wait four days until the body is used to the new time zone. Fortunately there is a short cut. It relies on two things-the power of the stomach to regulate the timing of other events, and the pharmacological actions of coffee. The basic assumptions are:

Coffee delays the body clock in the morning, and advances it at night. Coffee at mid-afternoon is neutral. Protein in meals stimulates wakefulness, while carbohydrates promote sleep. Putting food into an empty stomach helps synchronize the body clock.

46. What is jet lag associated with?

  A. Psychological change.            B. Physiological change.

  C. Inexperience of rapid travel.       D. Unfamiliar environment.

47. What helps us to adjust to a 24-hour rhythm?

  A. Alarm clock.                   B. Suprachiasmatic nucleus in our brain.

  C. Signals from outside of the body.   D. Our senses and stomachs.

48. What do we know from the fifth paragraph?

  A. A person moving to a different time zone will suffer from high blood pressure.

  B. A person moving to a different time zone will sweat a lot.

  C. Moving to a different time zone will affect both palm sweat and blood pressure.

  D. If the rhythm of blood pressure and palm sweat are not in step, there will be jet lag.

49. What should we do if we want to stay awake?

  A. To take coffee at three o’clock in the afternoon.

  B. To have meals that contain lots of protein.

  C. To have some carbohydrate drinks.

  D. To stop putting food into our stomach.

50. How can we cure jet lag?

   A. To sleep for days.      B. To wait for self-recovery.

   C. To drink tea.           D. To get something to eat.

If you want to keep healthy, you should have good habits. What is a habit? It is something we do very often. We don’t even think when we do it. It has become a part of our lives.

“Early to bed, early to rise makes a man healthy, wealthy and wise.” This is an old English saying. Do you know what it means? It means that we must go to bed early at night and get up early in the morning. If we do, we shall be healthy, rich and clever.

Is this true? Perhaps it is. We know the body must have enough sleep. Boys and girls need eight or nine hours’ sleep every day.

Some people go to bed late at night and get up late in the morning. This is a very bad habit. Then you will not think or do your work well. Of course, you can’t be healthy, wealthy or wise.

When we get up early in the morning, we can go out and do morning exercises. Exercise means doing things with the body. Walking, running jumping, swimming, and playing ball games are all exercise. If we don’t exercise, our body will become weak.

Exercise helps the blood (血液) to move around inside our body. Blood takes food to all parts of our body.

Our body also needs air to breathe. Without air, we will die. We must have lots of clean fresh air if we want to be healthy. That is why many people like to go out to do morning exercise.

1.From the passage we know that it is good for our health to ____ .

2.How long should young boys and girls need to sleep a day?

3.If we want to keep healthy, we must ____ .

4.Which of the following habits is NOT GOOD?

5. Which sport is NOT mentioned in the passage?

认真阅读下面短文，并在表格内的空白处填上一个合适的单词，注意：每空一词。

The average human experiences a lot of dreams while they sleep at night. But what exactly do they mean? The following explanations deal with four most common dreams and some of the possible meanings behind them, according to experts. Please note that, while certainly interesting, dream analysis is a highly subjective(主观的) field of study.

         Dreams about being chased (追逐)

         Dreaming about being chased generally means you may be avoiding a person or something painful, annoying or fearful.

         It could be a reminder that trying to avoid the problem could lead to more such dreams. Most people dream about being chased at one point or another. It’s both common and natural.

         Dreams about death

         According to Jeffrey Sumber, a psychotherapist (精神治疗师) and author, dreams about death often indicate “the ending of something, whether that’s a job or a relationship”. He suggests a dream about death can also indicate attempts to remove anxiety or anger. These dreams don’t suggest a person will actually die, he explains.

         There are no tricks when it comes to avoiding such dreams. The only way is to do our inner work and make peace with it.

         People who have dreams about death tend to be those who are entering an uncertain period in their life. It could be a life-changing event that creates anxiety and fear of the unknown.

         Dreams about falling

         Dreaming about falling can have a physiological basis, according to Cathleen O’ Connor, Ph. D. As the body goes deep into sleep and the nervous system begins to be quiet, blood pressure and heart rate drop and this change can cause a falling dream.

         O’Connor says that dreaming about falling is the mind’s way of warning the dreamer of a situation in his or her waking life where they feel out of control.

         “If dreams of falling bring feelings of fear, you should realize that the goal is not to avoid them but rather to work with those dreams in your waking state and deal with the fear so you can regain your balance,” O’ Connor says.

         Dreams about celebrities (名人)

         “Celebrities carry some kind of message that’s associated with personal achievements or lack,” says Shelley Smith, founding director of the Yoga Health & Therapy Center. “A person dreaming about a celebrity is looking for inspiration … or some characteristic that is associated with that celebrity.

         “That’s one of the features of dream images, and they are not under our control,” Smith says. “Your experience while you’re sleeping is coming from a place that’s totally unconscious (无意识的).”

         “There is no one group that we can say has this particular dream more than another,” she says, “The image is energetic and specific to what the person’s need is. For example, accomplishment, health, and rising to the top --- whatever is associated with that celebrity.

Winter in the north is usually very cold and it is important to avoid colder-related injuries such as frostbite(冻伤) and hypothermia(体温降低)．Frostbite is damage that happens when skin is exposed to extreme cold for too long．It mainly happens on the hands，feet，nose，and ears and some will bring permanent damage．Hypothermia is a serious medical condition caused by serious cold．It happens when the body cannot produce as much heat as it loses．If not treated，it can be deadly．
The best way to avoid cold-related injuries is to be prepared for the outdoors．Here is a simple way to remember four basic steps to staying warm．Think of COLD．
The C stands for cover．Wear a hat and scarf to keep heat from escaping through the head，neck，and ears．And wear mittens instead of gloves．Mittens are a type of glove that does not have separate parts for each finger．Gloves may not keep hands as warm because they separate the fingers．
The O stands for overexertion(过分用力)．Avoid activities that will make you sweaty．Wet clothes and cold weather are a bad mix．
L is for layers．Wearing loose，lightweight clothes，one layer on top of another, is better than single heavy layer clothing．Also，make sure outerwear is made of water resistant and tightly knit material．
The last letter D stands for dry．In other words，stay as dry as possible．Pay attention to the places where snow can enter, like the tops of boots．the necks of coats and the wrist areas of mittens．
And there are a couple of other things to keep in mind，one for children and the other for adults．Eating snow might be fun but it lowers the body's temperature．And drinking alcohol might make a person feel warm，but what it really does is weaken the body's ability to hold heat．
67．Both frostbite and hypothermia        ．
A．are injuries caused by extreme cold
B．may happen on the hands，feet，nose and ears
C．may cause uncontrollable shaking and slow breathing
D．may be deadly injuries
68．Mittens can keep your hands warmer than gloves because           ．
A．they are thicker                     B．they are made of better materials
C．they don't separate your fingers        D．they separate your fingers
69．      can help you avoid cold-related injuries．
A．Trying your best to exercise until you get sweat
B．Wearing layers of loose，lightweight clothes
C．Drinking alcohol to make you feel warm
D．Wearing a single heavy layer of clothing
70．Overexertion should be avoided because         ．
A．it may exhaust you       B．it may make you hungry
C．it may make you sweat     D．it may lower your body temperature

Medical drugs sometimes cause more damage than they cure. One solution to this problem is to put the drugs inside a capsule, protecting them from the body—and the body from them—until they can be released at just the right spot. There are lots of ways to trigger(引发) this release, including changing temperature, acidity, and so on. But triggers can come with their own risks—burns, for example. Now, researchers in California have designed what could be a harmless trigger to date: shining near-infrared light (NIR,近红外线) on the drug in the capsule.
The idea of using light to liberate the drug in the capsule isn't new. Researchers around the globe have developed polymers (聚合物) and other materials that begin to break down when they absorb either ultraviolet (UV,紫外线) or visible light. But tissues also readily absorb UV and visible light, which means the drug release can be triggered only near the skin, where the light can reach the capsule. NIR light largely passes through tissues, so researchers have tried to use it as a trigger. But few compounds(化合物) absorb NIR well and go through chemical changes.
That changed last year when Adah Almutairi, a chemist at the University of California, San Diego, reported that she and her colleagues had designed a polymer that breaks down when it absorbs NIR light. Their polymer used a commercially available NIR-absorbing group called o-nitrobenzyl (ONB). When they catch the light, ONB groups fall off the polymer, leading to its breakdown. But ONB is only a so-so NIR absorber, and it could be poisonous to cells when it separates from the polymer.
So Almutairi and her colleagues reported creating a new material for capsules that's even better. This one consists of a long chain of compounds called cresol groups linked in a polymer. Cresol contains reactive(易反应的) components that make it highly unstable in its polymeric form, a feature Almutairi and her colleagues use to their advantage. After polymerizing the cresols, they cap each reactive component with a light-absorbing compound called Bhc. When the Bhcs absorb NIR light, the reactive groups are exposed and break the long polymer into two short chains. Shining additional light continues this breakdown, potentially releasing any drugs in the capsule. What's more, Almutairi says, Bhc is 10 times better at absorbing NIR than is ONB and is not poisonous to cells.
【小题1】According to the passage, which of the following could be the best trigger?