题目内容

Flying over a desert in an airplane, two scientists looked down with trained eyes at trees and bushes. After an hour's flight one of the scientists wrote in his notebook, "Look here for probable metal." Walking across hilly ground, four scientists reported, "This ground should be searched for metals." From an airplane over a hilly wasteland a scientist sent back by radio one word "Uranium".

    None of the scientists had X-ray eyes: they had no magic powers for looking down below the earth's surface. They were merely putting to use one of the newest methods of locating minerals in the ground -- using trees and plants as signs that certain minerals may lie under the ground on which the trees and plants are growing.

    This newest method of searching for minerals is based on the fact that minerals deep in the earth may affect the kind of bushes and trees that grow on the surface.

    At Watson Bar Creek, a mineral search group gathered bags of tree seeds. Boxes were filled with small branches from the trees. Roots were dug and put into boxes. Each bag and box was carefully marked. In a scientific laboratory the parts of the forest trees were burned to ashes andtested. Each small part was examined to learn whether there were minerals in it.

    Study of the roots, branches and seeds showed no silver. But there were small amount of gold in the roots and a little less gold in the branches and seeds. The seeds growing nearest to the tree trunk had more gold than those growing on the ends of the branches.

    If the trees indicated that there was no gold in the ground, the scientists wouldn't spare money to pay for digging into the ground.

Scientists were flying over a desert or a hilly wasteland or a mountain region to ________.

A. train their eyes B. study the trees   C. look for gold         D. search for minerals

The study of trees, branches and roots indicated that __________.

A. there were larger amounts of gold in the branches far from the tree trunk than in the seeds

B. there were smaller amounts of gold in the tree roots deep in the ground than in the branches

C. there were larger amounts of gold in the seeds growing closer to the tree trunk than in the seeds farther from it

D. there were larger amounts of gold in the branches than in the leaves on the ends of the branches

Which of the following is NOT mentioned as part of a tree that can help the searchers?

A. Leaves.          B. Roots.            C. Branches.           D. Seeds.

Which of the following might be the best title for this passage?

A. Scientists searching for treasure with special equipment.

  B. New methods of doing geological study.

C. Gold could be found in trees and plants.

D. A new method of searching for minerals.

【小题1】D

【小题2】C

【小题3】A

【小题4】D


解析:

【小题1】 推理判断题。科学家的最终目的是寻找地下矿物,而且文章中提到的metal,gold,silver,uranium都属于minerals的范畴,故选D。

【小题2】 推理判断题。答此题的关键在于理解文章第五段最后一句话The seeds growing nearest to the tree trunk had more gold thant those growing on the ends of the branches,这句话指出,长得离树干最近的种子比长在树枝末端的种子的含金量高,故可推断出,种子离树干越近,含金量就越高,因此选C。

【小题3】 细节理解题。根据文章第四段可知,只有leaves没有提到,故选A。

【小题4】 主旨大意题。文章主要讲述了探测矿藏韵一种新方法,故选D。文章并没介绍一种特殊的探矿设备,故不选A。

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A. can cause difficulties in speaking

B. can make people feel tired for a few weeks?

C. can be only found in flight attendants

D. can be caused by flying over several time zones?

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A. the conclusion is refused by many scientists?

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A. The cause of jet lag.?

B. A story of a group of flight attendants.?

C. The importance of having enough rest after flights.?

D. A research about the effects of jet lag on the brain.??

A new study says one part of the human brain may become smaller as the result of a condition known as jet lag. Jet lag results from flying long distances in an airplane. People with jet lag may feel extremely tired for several days. They may also have problems thinking clearly and remembering.
Recently a researcher at the University of Bristol in Britain reported the findings of his jet lag study, which involved twenty young women who worked for international airlines. They had served passengers on airplanes for five years. These flight attendants flew across many countries and at least seven time zones. In the study, the flight attendants had different amounts of time to recover from jet lag. Half the women spent five days or fewer in their home areas between long flights. The other half spent more than fourteen days in their home areas.
The researcher took some saliva from the women”s mouths to measure levels of a hormone(荷尔蒙) that increases during stress(紧张). He tested them to see if they could remember where black spots appeared on a computer screen. And he took pictures of their brains to measure the size of the brain”s temporal lobes(脑叶).
It was found that the women who had less time between flights had smaller right temporal lobes. This area of the brain deals with recognizing and remembering what is seen. The same group performed worse and had slower reaction times on the visual memory test. And their saliva samples showed higher levels of stress hormones.
The researcher believes the brain needs at least ten days to recover after a long trip. He says airline workers told him their ability to remember got worse after working on planes for about four years. Other studies have shown that increased feelings of stress can cause a loss of cells in the part of the brain that controls memory.
Scientists say more tests are needed to study the effects of jet lag on the brain. They want to find out if too much jet lag could permanently (永久性的) affect memory.
【小题1】According to the text, jet lag .

  1. can cause difficulties in speaking
  2. can make people feel tired for a few weeks
  3. can be only found in flight attendants
  4. can be caused by flying over several time zones
【小题2】It can be inferred from the text that .
  1. the conclusion is refused by many scientists
  2. scientists fear that this research is not done properly
  3. the scientific conclusion needs the support from many tests
  4. every women who were examined in the research were mot healthy
【小题3】From the result of the research we can see that .
  1. the women who have longer rest at home show better memory
  2. the women who fly in short time have smaller right temporal lobes
  3. the women who have longer flights fail the memory test
  4. the women who rest more than 14 days produce less hormones
【小题4】What is the subject discussed in the text?
  1. The cause of jet lag.
  2. A story of a group of flight attendants.
  3. The importance of having enough rest after flights.
  4. A research about the effects of jet lag on the brain.

Flying over a desert in an airplane, two scientists looked down with trained eyes at trees and bushes.After an hour's flight, one of the scientists wrote in his notebook, "Look here for probable metal." Walking across hilly ground, four scientists reported, "This ground should be searched for metals." From an airplane over a hilly wasteland a scientist sent back by radio one word "Uranium".

None of the scientists had X-ray eyes: they had no magic powers for looking down below the earth's surface.They were merely putting to use one of the newest methods of locating minerals in the ground -- using trees and plants as signs that certain minerals may lie under the ground on which the trees and plants are growing.

This newest method of searching for minerals is based on the fact that minerals deep in the earth may affect the kind of bushes and trees that grow on the surface.

At Watson Bar Creek, a mineral search group gathered bags of tree seeds.Boxes were filled with small branches from the trees.Roots were dug and put into boxes.Each bag and box was carefully marked.In a scientific laboratory the parts of the forest trees were burned to ashes and tested.Each small part was examined to learn whether there were minerals in it.

Study of the roots, branches and seeds showed no silver.But there were small amounts of gold in the roots and a little less gold in the branches and seeds.The seeds growing nearest to the tree trunk had more gold than those growing on the ends of the branches.

If the trees indicated that there was no gold in the ground, the scientists wouldn't spare money to pay for digging into the ground.

1.Scientists were flying over a desert or a hilly wasteland or a mountain region to _____.

A.train their eyes

B.study the trees

C.look for gold

D.search for minerals

2.The study of trees, branches and roots indicated that ______.

A.there were larger amounts of gold in the branches far from the tree trunk than in the seeds

B.there were smaller amounts of gold in the tree roots deep in the ground than in the branches

C.there were larger amounts of gold in the seeds growing closer to the tree trunk than in the seeds farther from it

D.there were larger amounts of gold in the branches than in the leaves on the ends of the branches

3.Which of the following is NOT mentioned as part of a tree that can help the searchers?

A.leaves

B.roots

C.branches

D.seeds

4.Which of the following might be the best title for this passage?

A.Scientists searching for treasure with special equipment.

B.New methods of doing geological study.

C.Gold could be found in trees and plants.

D.A new method of searching for minerals.

 

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