Have you ever noticed that your fingertips are winked when you’ve just finished swimming or washing dishes? It seems as if your hands have aged 30 years i a second. But is this an accident? Or is it something that nature has built into our bodies?

If your finger’s wrinkling up had no use at all, “ it wouldn’t need to.” Professor Tom Smulders from Newcastle University, UK, told BBC News. By studying wet fingers closely, Smulders and his partners found that the wrinkles looked a bit like the patterns on the car tire or o the bottom of the running shoes. So they made a guess that wrinkles on fingers might be able to help the hand hold things more tightly.

To test this, researchers asked 20 people to pick up marbles from water with their hands. But before they started, some of the people had to keep their hands in water for half an hour.

The researchers found that the people with wrinkled fingers completed the task the task faster than those with dry hands. But when they were asked to move dry marbles, all the people performed equally well, no matter they had the wrinkled fingers or not.

Our ancestors might not have played with marbles, but wrinkled fingers could have made it easier for them to climb around in the wet forests and catch fish from rivers, researchers say.

Similarly, our toes also get wrinkled in water. This may have developed from our ancestor’s need to run on wet ground.

But the question is, if wrinkled fingers are so helpful, why don’t our hands just stay that way all the time? Researchers explained that wrinkling has its disadvantage: wet fingertips are far less sensitive than smooth ones, reducing our sense of touch.

26, What does the underlined world “this ” in the third paragraph refer to?

A. Wether fingers have wrinkles after they are put in water.

B. Wether wrinkled fingers can hold things more tightly.

C. Why keeping things in water makes them wrinkled.

D. Why wrinkles help hands hold things more tightly.

27, The test shows that ________.

A. winkled hands hold dry things more tightly than dry hands do.

B. dry hands hold dry things more tightly than wrinkled hands do.

C. winkled hands hold wet things more tightly than dry hands do.

D. dry hands hold wet things more tightly than wrinkled hands do.

28. What might be the disadvantage of wrinkled fingers?

A. They are too sensitive to be touched.

B. They might be more likely to get hurt.

C. They cannot hold things tightly enough.

D. They are not so sensitive as dry fingers.

26 B 細(xì)節(jié)題,this指代第二段中最后一句話

27 C細(xì)節(jié)題,答案在文章第三段

28 D細(xì)節(jié)題,文章是文章最后一句話

練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

科目:初中英語(yǔ) 來(lái)源: 題型:

根據(jù)短文內(nèi)容及所給首字母提示寫(xiě)出所缺單詞, 并將完整單詞填在下面對(duì)應(yīng)題號(hào)后的橫線上。
Air is very important to everything that lives. But the air we breathe is g  1  dirty. People all over the world are looking for w  2  to make it clean again.
Have you e  3  watched the smoke from chimneys(煙囪) rising high in the air? Have you s  4  the smoke from cars and trucks on roads or the smoke from planes? The smoke is not g  5  to breathe. If we want to keep healthy and strong, we need to breathe c  6   air.
W  7  more and more factories everywhere and more and more cars, trucks and planes, it is getting harder and harder to do with the air p  8 .
Scientists have a  9  taken actions to stop or slow down some of the things that make the air dirty. They will not stop working u  10  we have clean air again.
1.           2.           3.           4.           5.        
6.           7.           8.           9.           10.        

查看答案和解析>>

科目:初中英語(yǔ) 來(lái)源: 題型:


Air is very important to everything that lives. But the air we breathe is g【小題1】___ dirty. People all over the world are looking for w【小題2】___ to make it clean again.
Have you e【小題3】__ watched the smoke from chimneys rising high in the air? Have you s【小題4】__ the smoke from cars and trucks on roads or the smoke from planes? The smoke is not g【小題5】___ to breathe. If we want to keep well and strong, we need to breathe c【小題6】__ air.
W【小題7】___ more and more factories everywhere and more and more cars, trucks and planes, it is getting harder and harder to do with the air p【小題8】___.
Scientists have a【小題9】__ found ways to stop or slow down some of the things that make the air dirty. They will not stop working u【小題10】__ we have clean air again.

查看答案和解析>>

科目:初中英語(yǔ) 來(lái)源: 題型:

單詞拼寫(xiě)(共10小題,計(jì)10分)
根據(jù)下列句子及所給單詞的首字母,在答題紙上按題號(hào)寫(xiě)出各單詞的完全形式(每空限填一詞)。
【小題1】 Be careful. There is a wine b_______ on the table. You might break it.
【小題2】 The number after twenty-nine is t________.
【小題3】Have you e________ been to the Great Wall?
【小題4】It’s dangerous to d________ a car after you get drunk.
【小題5】Your parents are your f________ and mother.
【小題6】If a dream comes t________, it actually happens.
【小題7】W________ is the coldest season of the year.
【小題8】When snow f________, it comes down from the sky.
【小題9】It’s best to water plants either e________ in the morning or late at night.
【小題10】We don’t go to the c________ much for movies because we have a video.

查看答案和解析>>

科目:初中英語(yǔ) 來(lái)源:2010-2011學(xué)年江蘇省鎮(zhèn)江市初三上學(xué)期期末考試英語(yǔ)卷 題型:其他題

根據(jù)短文內(nèi)容及所給首字母提示寫(xiě)出所缺單詞, 并將完整單詞填在下面對(duì)應(yīng)題號(hào)后的橫線上。

  Air is very important to everything that lives. But the air we breathe is g  1   dirty. People all over the world are looking for w  2   to make it clean again.

Have you e  3   watched the smoke from chimneys(煙囪) rising high in the air? Have you s  4   the smoke from cars and trucks on roads or the smoke from planes? The smoke is not g  5   to breathe. If we want to keep healthy and strong, we need to breathe c  6   air.

W  7   more and more factories everywhere and more and more cars, trucks and planes, it is getting harder and harder to do with the air p  8  .

Scientists have a  9   taken actions to stop or slow down some of the things that make the air dirty. They will not stop working u  10   we have clean air again.

1.            2.            3.            4.            5.        

6.            7.            8.            9.            10.        

 

查看答案和解析>>

科目:初中英語(yǔ) 來(lái)源: 題型:

根據(jù)首字母 及上下文提示完成對(duì)話

A: Have you e_80___ been to Tokyo?

B: No, I have n___81__ been there before. But this summer I will go there with my parents.

   A: I am s__82__ you will like it. My uncle u__83___ to work in Tokyo. But now he has g__84___to Paris for an i___85___ meeting. He will give a talk about how to p____86___ whales next week.

   B: Paris? That is a really wonderful city with a very b__87_______ view.

   A: R___88____? H__89___ I wish I could go there!

   80____________81_____________82______________83______________84_____________

85____________86______________87_____________88______________89_____________

查看答案和解析>>

同步練習(xí)冊(cè)答案