Yawning sends out certain messages -either “Oh ,this movie is so boring” or “I probably need to get some sleep”. But did you know that a yawn can also help your brain to cool down when it is overheated?
A new study, led by a research team at Princeton University, has indicated that yawning could be the brain’s natural way of regulating temperature. People yawn more often when the temperature outdoors is lower than their body temperature but are less likely to yawn when it is hotter outdoors, according to Sciencedaily. com.
The research team did an experiment on 160 people, 80 in summer and 80 in winter, to examine how often they yawned at different air temperatures. The study found that people yawned more often in winter than in summer. Scientists say that when the air temperature is lower outside the body, there is heat exchange between the overheated brain and the cool air. But when the air temperature is higher than or equal to the body, people are less likely to yawn because the hot air they breathe in will make the brain even hotter.
When people yawn, their jaw is also stretched ,which increases blood flow and may also help cool the brain
The study showed that the amount someone yawned could be related to the amount of time they spent outside. The longer they spent outside in summer, the less they yawned. Nearly 40 percent of participants yawned within their first five minutes outside, but after that the percentage was reduced to less than 10 percent.
However, the result was the opposite in winter. The number of people who yawned increased when they spent more than five minutes outdoors. But the change was only slight compared to summertime.
According to Gallup, this is the first report to show that yawning frequencies change depending on season. This could help us to understand better the way our brains work. It may also help us understand the reason why frequent yawning can sometimes be a sign of brain disease.
【小題1】The purpose of the experiment is ______.

A. to prove people yawn in winter and in summer equally
B. to indicate brain can regulate temperature naturally
C. to find the frequency of people’s yawning
D. to show the real reason why people yawn
【小題2】The information we get from Paragraphs 5 and 6 is that ______.
A. longer outdoor summertime results in more yawns
B. yawning frequency changes with outdoor time
C. yawning frequency increases with outdoor time
D. longer outdoor wintertime leads to fewer yawns
【小題3】Acorrding to the text ,people yawn more often ______.
A,  when the air temperature is lower outside the body
B.  when the hot air breathed in makes the brain hotter
C. when the air temperature is higher than the body
D. when the air temperature is equal to the body
【小題4】What could be the best title for the text?
A. Yawning Is A Sign of Brain Disease
B. Yawning Carries Some Information
C. Yawning Benefits Your Body
D. Yawning Cools Your Brain


【小題1】C
【小題2】B
【小題3】A
【小題4】D

解析試題分析:本文介紹了大腦調(diào)節(jié)溫度的自然方法是打呵欠。當(dāng)體溫高于室溫時,人們打呵欠的頻率會增加,反之會降低,同時,打呵欠的頻率變化取決于季節(jié),夏季時人們在戶外時前五分鐘有近40%的參加實驗的人會打呵欠,之后會降到不到10%,而冬季前五分鐘打呵欠的人比夏季多,但之后和夏季的數(shù)據(jù)只有輕微變化。
【小題1】細(xì)節(jié)題:根據(jù)第三段中“ to examine how often they yawned at different air temperatures.”檢查在不同的溫度下打呵欠的頻率。故選C。
【小題2】推理題:閱讀第五第六段可知在戶外打呵欠的頻率有所改變。夏季時人們在戶外時前五分鐘有近40%的參加實驗的人會打呵欠,之后會降到不到10%,而冬季前五分鐘打呵欠的人比夏季多,但之后和夏季的數(shù)據(jù)有輕微變化。故選B。
【小題3】細(xì)節(jié)題:根據(jù)第二段中“ People yawn more often when the temperature outdoors is lower than their body temperature”當(dāng)室外溫度低于體溫時人們會更多地打呵欠。故選A。
【小題4】推理題:閱讀文章可知第二段中“A new study, led by a research team at Princeton University, has indicated that yawning could be the brain’s natural way of regulating temperature”普林斯頓大學(xué)的一個研究小組的一項最新研究表明打呵欠是大腦調(diào)節(jié)溫度的自然方式,是文章主旨,全文圍繞這一主題展開舉例論述。故選D。
考點:考查科普類閱讀

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【小題1】By touching things,               .

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【小題5】Which of the following is NOT true?
A.Touching is helping us to see better.  
B.Our skips may help us enjoy music.  
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