题目内容

【题目】The first place to visit for foreign friends is the Great Wall, which is the __________ of China and one of the seven wonders in the world.

A. symbol B. sign

C. signal D. mark

【答案】A

【解析】句意:外国友人最想参观的地方是长城,她是中华民族的象征,也是世界七大奇观之一。symbol象征,尤其指用有形实物代抽象的实体;sign符号,代表有固定意义的符号或标记;signal信号,被用作交通、通讯的指示或传递消息的一种手势或有色的光;mark标记,为某一特定目的而做的标记或有意、无意留下的痕迹。综上所述选A

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【题目】One day, Amy is digging in the ground for a potato when along comes Tom. Seeing that there is no one in sight, Tom starts to scream. Tom’s angry mother rushes over and drives Amy away. Once his mum has gone, Tom helps himself to Amy’s potato.

We’ve all experienced similar annoying tricks when we were young—the brother who stole your ball and then got you into trouble by telling your parents you had hit him. But Amy and Tom are not humans. They’re African baboons(狒狒). __【1】___

Tom’s scream and his mother’s attack on Amy could have been a matter of chance, but Tom was later seen playing the same tricks on others. _2__

Studying behavior like this is complicated but scientists discovered apes(猿) clearly showed that they intended to cheat and knew when they themselves had been cheated. __3___ An ape was annoying him, so he tricked her into going away by pretending he had seen something interesting. When she found nothing, she “walked back, hit me over the head with her hand and ignored me for the rest of the day.”

Another way to decide whether an animal’s behavior is deliberate is to look for actions that are not normal for that animal. A zoo worker describes how an ape dealt with an enemy. “He slowly stole up behind the other ape, walking on tiptoe. When he got close to his enemy, he pushed him violently in the back, then ran indoors.” Wild apes do not normally walk on tiptoe. __4__ But looking at the many cases of deliberate trickery in apes, it is impossible to explain them all as simple copying.

It seems that trickery does play an important part in ape societies. ___5__ Studying the intelligence of our closest relative could be the way to understand the development of human intelligence.

A. An amusing example of this comes from a psychologist working in Tanzania.

B. And playing tricks is as much a part of monkey behavior as it is of human behavior.

C. So the psychologists asked his colleagues if they had noticed this kind of trickery.

D. Of course it’s possible that it could have learnt from humans that such behavior works, without understanding why.

E. This use of a third individual to achieve a goal is only one of the many tricks commonly used by baboons.

F. The ability of animals to cheat may be a better measure of their intelligence than their use of tools.

G. In most cases the animal probably doesn’t know it is cheating.

【题目】【原创】Humans are well-equipped for life on Earth. But in space, it is different. Low or zero gravity changes how the blood flows and causes motion sickness, muscle loss and tiredness. Weightlessness can also cause bone loss. But scientists are experimenting with little worms to better understand how space travel affects astronauts.

The millimeter-long worm is called C. elegans. The see-through worm is often used in medical studies because its life is only about two weeks long. Seventy percent of its DNA is the same as human DNA.

Sabanayagam is a scientist, who built a micro-gravity simulator to test how C. elegans would perform in the actual zero gravity of space.

Scientists put the worms into the simiulator full of water. After a week they take out the worms. They look for changes in the worms' epigenome,which are chemical markers that tell the DNA in the cells how to perform. The epigenome can be changed by the environment. And those changes pass from one generation of worms to the next.

"When the worms are in a liquid environment, some epigenomic marks remain even when we take the animal out of the liquid environment and put it back into normal ground conditions. So its offspring keeps this epigenomic memory of the parents' liquid environment or microgravity environment."

The information the scientists have gathered suggests that the epigenomic marks appear during the early part of a worm’s life.

Mr. Sabanayagam says he thinks scientists can find genes in the human similar to those in the worms that responded to microgravity and scientists could possibly observe those genes closely when astronauts travel in space.

Sabanayagam expects C. elegans to visit the International Space Station within two years. He says he hopes information gathered from the worm studies can be used to develop simple, low-cost and quick tests to measure an astronaut's health.

【1】What does the underlined word zero gravity” mean?

A. Seasickness B. Muscle loss

C. Weightlessness D. Tiredness.

【2】 From the passage we can know C. elegans _____.

A. has exactly the same DNA as human

B. is harmful to human

C. is often used in agricultural research

D. has a short life period

【3】Why do scientists experiment with C. elegans?

A. Because it has strong life power in water.

B. Because they want to find how space travel affects astronauts

C. Because the worm will be taken into space.

D. Because they want to find what its DNA like.

【4】What is Sabanayagam’s attitude toward the result of the experiment?

A. Hopeful and satisfied.

B. Doubtful and unsure.

C. Sad and disappointed.

D. Surprised and unbelievable.

【5】Which section of a newspaper can you find the passage?

A. Education. B. Science.

C. Advertisement. D. Entertainment.

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