If your head is overheating, you are very likely to yawn(打哈欠) soon, according to a new study that has found the main purpose of yawning is to control brain temperature. The study explains several mysteries about yawning, such as why it’s most commonly done just before and after sleeping, why certain diseases lead to too much yawning, and why breathing though the nose often stops yawning.
“Brains are like computers,” Andrew Gallup, a researcher in the department of Biology at Binghamton University who led the study, said. “They operate best when cool.”
He and his co-workers Micheal Miller and Anne Clark did researches on yawning in parakeets(长尾小鹦鹉) , which have relatively large brains, live wild in Australia, often experience temperature changes, and, most importantly, do not yawn when others yawn, as humans and some other animals do.
For the study, the scientists put parakeets under three different conditions: increasing temperature, high temperature and normal temperature. While the frequency(频率) of yawns did not increase under the latter two conditions, it increased greatly when the researchers increased the temperature.
It’s now believed yawning operates like a radiator(散热器).
If air in the atmosphere is cooler than the brain and body temperatures, taking it in quickly cools blood, which in turn cools the brain. The new findings also explain why tired people often yawn. Both tiredness and sleep loss can increase brain temperature, while yawning can cool down the brain.
In the future, researchers may focus more on brain temperature and its role in diseases and their symptoms. But the new study on yawning changes the popular idea that yawns are just signs of getting tired of something.
49. What’s the best title for the passage?
A. Why don’t people yawn at normal temperature?
B. The yawn explained—it cools your brain.
C. Yawning operates like a radiator.
D. The cause of yawning—finally found out.
50. The main reason why researchers chose parakeets to do the research is that parakeets______.
A. have very large brains                
B. live wild in Australia
C. are not affected by others’ yawning       
D. experience frequent temperature changes
51. The writer may suggest doing all of the following to stop yawning EXCEPT______.
A. breathing through the nose          
B. turning up the heat
C. enjoying some cool wind               
D. putting a cold towel on your forehead
52. In which section of a newspaper would you most probably read this passage?
A. Discovery.        B. Education.         C. Health.              D. Mystery.

If your head is overheating, you are very likely to yawn(打哈欠) soon, according to a new study that has found the main purpose of yawning is to control brain temperature. The study explains several mysteries about yawning, such as why it’s most commonly done just before and after sleeping, why certain diseases lead to too much yawning, and why breathing though the nose often stops yawning.

“Brains are like computers,” Andrew Gallup, a researcher in the department of Biology at Binghamton University who led the study, said. “They operate best when cool.”

He and his co-workers Micheal Miller and Anne Clark did researches on yawning in parakeets(长尾小鹦鹉) , which have relatively large brains, live wild in Australia, often experience temperature changes, and, most importantly, do not yawn when others yawn, as humans and some other animals do.

For the study, the scientists put parakeets under three different conditions: increasing temperature, high temperature and normal temperature. While the frequency(频率) of yawns did not increase under the latter two conditions, it increased greatly when the researchers increased the temperature.

It’s now believed yawning operates like a radiator(散热器).

If air in the atmosphere is cooler than the brain and body temperatures, taking it in quickly cools blood, which in turn cools the brain. The new findings also explain why tired people often yawn. Both tiredness and sleep loss can increase brain temperature, while yawning can cool down the brain.

In the future, researchers may focus more on brain temperature and its role in diseases and their symptoms. But the new study on yawning changes the popular idea that yawns are just signs of getting tired of something.

49. What’s the best title for the passage?

A. Why don’t people yawn at normal temperature?

B. The yawn explained—it cools your brain.

C. Yawning operates like a radiator.

D. The cause of yawning—finally found out.

50. The main reason why researchers chose parakeets to do the research is that parakeets______.

A. have very large brains                 

B. live wild in Australia

C. are not affected by others’ yawning       

D. experience frequent temperature changes

51. The writer may suggest doing all of the following to stop yawning EXCEPT______.

A. breathing through the nose           

B. turning up the heat

C. enjoying some cool wind               

D. putting a cold towel on your forehead

52. In which section of a newspaper would you most probably read this passage?

A. Discovery.        B. Education.         C. Health.              D. Mystery.

Have you ever walked outside thinking it was one temperature but quickly discovered it felt colder? That is because of the “wind chill” effect.
Wind chill is how cold people and animals feel when they are outside, not the actual temperature on the thermometer(温度计). It is based on how quickly your body loses heat when it is exposed to wind and cold. When the wind is strong, your body quickly loses heat, making the temperature of your skin drop.
When scientists first started calculating wind chill, they used research conducted in 1945 by explorers to Antarctica who measured how quickly water froze outside.
But water freezes faster than exposed skin, so the wind chill index based on that data wasn’t accurate.
In 2001, the US government began to measure wind chill more precisely by testing how quickly people’s skin froze.
Twelve volunteers were placed in a chilled wind tunnel. Equipment was stuck to their faces to measure the heat flow from their cheeks, forehead, nose and chin while they walked three miles per hour on a treadmill(跑步机).
The experiment revealed how quickly exposed skin can be damaged, particularly unprotected areas like your fingers, toes, the tip of your nose and your ear lobes. In fact, 40 percent of your body heat can be lost through your head! Signs you might have frostbite(冻疮) are when the skin turns white or pale and you lose feeling in that area.
The information collected from the volunteers helped scientists work out the math to compute wind chill. It involves wind speed and air temperature.
If, for example, the temperature outside is zero degrees Fahrenheit and the wind is blowing at 15 miles per hour, the wind chill is calculated at 19 degrees below zero. At that wind chill temperature, exposed skin can freeze in 30 minutes.
You can find a calculation table at www.nws.noaa.gov/om/windchill/index.shtml.
Experts advise in cold weather that you wear loose-fitting, lightweight, warm clothing, worn on top of each other. Air caught between the clothes will keep you warm. The best cold-weather coats have head coverings made of woven material that keep out water. So next time the temperature drops and you want to play outside, listen to your parents when they tell you to wrap up warm!
【小题1】 According to the text, wind chill _______.

Have you ever walked outside thinking it was one temperature but quickly discovered it felt colder? That is because of the “wind chill” effect.
Wind chill is how cold people and animals feel when they are outside, not the actual temperature on the thermometer(温度计). It is based on how quickly your body loses heat when it is exposed to wind and cold. When the wind is strong, your body quickly loses heat, making the temperature of your skin drop.
When scientists first started calculating wind chill, they used research conducted in 1945 by explorers to Antarctica who measured how quickly water froze outside.
But water freezes faster than exposed skin, so the wind chill index based on that data wasn’t accurate.
In 2001, the US government began to measure wind chill more precisely by testing how quickly people’s skin froze.
Twelve volunteers were placed in a chilled wind tunnel. Equipment was stuck to their faces to measure the heat flow from their cheeks, forehead, nose and chin while they walked three miles per hour on a treadmill(跑步机).
The experiment revealed how quickly exposed skin can be damaged, particularly unprotected areas like your fingers, toes, the tip of your nose and your ear lobes. In fact, 40 percent of your body heat can be lost through your head! Signs you might have frostbite(冻疮) are when the skin turns white or pale and you lose feeling in that area.
The information collected from the volunteers helped scientists work out the math to compute wind chill. It involves wind speed and air temperature.
If, for example, the temperature outside is zero degrees Fahrenheit and the wind is blowing at 15 miles per hour, the wind chill is calculated at 19 degrees below zero. At that wind chill temperature, exposed skin can freeze in 30 minutes.
You can find a calculation table at www.nws.noaa.gov/om/windchill/index.shtml.
Experts advise in cold weather that you wear loose-fitting, lightweight, warm clothing, worn on top of each other. Air caught between the clothes will keep you warm. The best cold-weather coats have head coverings made of woven material that keep out water. So next time the temperature drops and you want to play outside, listen to your parents when they tell you to wrap up warm!

1. 1.

   According to the text, wind chill _______.

   1. A.
      means how fast exposed skin freezes
   2. B.
      doesn’t affect your head as much as other body parts
   3. C.
      changes according to the temperature on the thermometer
   4. D.
      changes from person to person depending on their health
2. 2.

   When might a person have frostbite according to the passage?

   1. A.
      When his skin turns red and he loses feeling in that area.
   2. B.
      When he is running faster and he is losing strength quickly.
   3. C.
      When his face is exposed and quickly loses heat even indoors.
   4. D.
      When his skin turns pale and he has no feeling in that area.
3. 3.

   What factors influence wind chill?

   1. A.
      A person’s body temperature and will speed.
   2. B.
      Wind speed and a person’s strength.
   3. C.
      Air temperature and wind speed.
   4. D.
      The location and air temperature.
4. 4.

   What can we conclude from the passage?

   1. A.
      It was in 1945 that scientists first began to calculate wind chill.
   2. B.
      Compared with water, people’s exposed skin freezes more slowly.
   3. C.
      The wind chill index based on Antarctica data is considered a standard.
   4. D.
      With the development of technology, many previous researches have been proven wrong.

第二节  信息匹配（共5小题，每小题2分，满分l0分）

根据短文内容，从下框的A—F选项中选出能概括每一段主题的最佳选项。选项中有一项为多余选项。（注意：E涂AB；F涂AC）

A．The effects of flu and its symptoms

B．Types of virus to cause flu

C．People’s attitudes toward flu

D．The cause of flu

E．The way that flu spreads

F．The methods to fight flu

61.

Flu (which is short for influenza) is a highly infectious disease，the cause of which is a very tiny organism known as a virus．Several types of flu are recognized，depending on the type of virus that causes the disease．

    62．

Flu Can often cause problems in breathing，and general infection of the lung．With elderly and weak people，these added complications often produce serious results．The virus, if not properly treated, can weaken the body so that patient may develop more serious illnesses，such as pneumonia and bronchitis．When people catch flu，they often complain of a headache or a sore throat．They usually have a fever and their temperature rises from the normal 37℃ (98.6℉) to about 39.5℃ (103℉)．Sometimes a person has a dry hacking cough and aching joints．

63．

Today many doctors use drugs that fight the disease．And scientists have also developed vaccines that help to prevent it．If the patient has proper treatment，and complete rest in bed，the virus is normally beaten within a week to ten days．

64．

How does flu spread so quickly? When the infected person breathes out．sneezes or coughs，he gives out droplets of moisture in the breath from his mouth or nose．These remain in the air for some time．Flu viruses are present in these droplets．If a person sneezes in a crowd or poorly ventilated place，such as a lift，viruses can easily be carried from all infected person to a healthy person．This is known as droplet infection．The healthy person will breathe in the viruses given out by the infected person．

65．

There are three main types of virus that cause flu，which are called type A, B and C. Type A is the most powerful of the three，and undergoes minor changes in its genetic material every few years．The new form of the virus is called a strain．The new strain is not affected by the current vaccines. It is said to be“resistant”to them．So doctors must be continually producing new vaccines to combat the new strains of virus．