How would you like to sleep with one half your brain asleep and the other half awake? Dolphins sleep this way. Recently, scientists at Indiana State University have discovered that ducks sleep this wa 题目和参考答案——青夏教育精英家教网—

题目内容

How would you like to sleep with one half your brain asleep and the other half awake? Dolphins sleep this way. Recently, scientists at Indiana State University have discovered that ducks sleep this way too. They found that ducks sleep half awake so they can rest and watch for danger at the same time.

After putting their ducks in a row and videotaping them, some researchers found ducks on the end of each row spent more time asleep with one eye open, apparently looking for predators.

“The more the ducks felt threatened ,the more they slept with one eye open,” said lead author Niels C．Rattenborg, a graduate student at Indiana State University, Terre Haute.” the unique aspect is not that they do it, but that they control it. When they sleep at the edge of a group, they tend to realize greater danger, so they spend more time sleeping with one half of their brain.” Ducks with one eye open were still awake enough to detect predators, said the authors of the study, which appears today in the Journal Nature.

The researchers studied four groups of four ducks held in plastic boxes, which were arranged in a row. Ducks on the end were found to sleep with one eye open 31.8 per cent of the time, compared to 12.4 percent of the time for ducks in the central position.

Also, ducks in the central position did not open one eye more than the others, while ducks on each end kept the eye facing away from the group open 86.2 per cent of the time. Brain wave readings of the ducks showed that the half of the brain receiving signals from the closed eye indicated that half of the brain was sleeping. Signals from the half of the brain receiving signals from the open eye showed a state between fully awake and asleep.

1．A predator is most likely to be .

A．a scientist who does research work on animals

B．a human being who looks after and feeds ducks

C．an animal that hunts ,kills and eats other animals

D．an animal that is likely to be friends with ducks

2．Ducks at the end of each row sleep with one eye open because .

A．they are looking for food

B．they want to enjoy the scenery

C．they are watching out for danger

D．they are unique in their sleeping habit

3．How many ducks were used in the experiment?

A．Four. B．Eight. C．Twelve. D．Sixteen.

4．Which of the following is true according to the passage?

A．Ducks on the northern end of a row would keep their eye facing the south open.

B．Ducks with less sense of duty usually choose to stay in the center of a row.

C．Ducks with one eye open at the edge can still enjoy a certain degree of sleep.

D．A video tape recorder was the only electronic device used in the experiment.

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相关题目

How could we possibly think that keeping animals in cages in unnatural environments－mostly for entertainment purposes－is fair and respectful?

Zoo officials say they are concerned about animals. However, most zoos remain “collections” of interesting “things” rather than protective habitats (栖息地). Zoos teach people that it is acceptable to keep animals bored, lonely, and far from their natural homes.

Zoos claim (声称) to educate people and save endangered species(物种), but visitors leave zoos without having learned anything meaningful about the animals’ natural behavior, intelligence, or beauty. Zoos keep animals in small spaces or cages, and most signs only mention the species’ name, diet, and natural range(分布区). The animals’ normal behavior is seldom noticed because zoos don’t usually take care of the animals’ natural needs.

The animals are kept together in small spaces, with no privacy and little opportunity for mental and physical exercise. This results in unusual and self-destructive behavior called zoochosis. A worldwide study of zoos found that zoochosis is common among animals kept in small spaces or cages. Another study showed that elephants spend 22 percent of their time making repeated head movements or biting cage bars, and bears spend 30 percent of their time walking back and forth, a sign of unhappiness and pain.

Furthermore, most animals in zoos are not endangered. Captive breeding(圈养繁殖)of endangered big cats, Asian elephants, and other species has not resulted n their being sent back to the wild. Zoos talk a lot about their captive breeding programs because they do not want people to worry about a species dying out. In fact, baby animals also attract a lot of paying customers. Haven’t we seen enough competitions to name baby animals?

Actually, we will save endangered species only if we save their habitats and put an end to the reasons people kill them. Instead of supporting zoos, we should support groups that work to protect animals’ natural habitats.

64. How would the author describe the animals’ life in zoos?

A. Dangerous. B. Unhappy. C. Natural. D. Easy.

65. In the state of zoochosis, animals _________.

A. remain in cages B. behave strangely

C. attack other animals D. enjoy moving around

66. What does the author try to argue n the passage?

A. Zoos are not worth the public support.

B. Zoos fail in their attempt to save animals.

C. Zoos should treat animals as human beings.

D. Zoos use animals as a means of entertainment.

67. The author tries to persuade readers to accept his argument mainly by _____.

A. pointing out the faults in what zoos do B. using evidence he has collected at zoos

C. questioning the way animals are protected D. discussing the advantages of natural habitats

68. Although he argues against zoos, the author would still agree that _______.

A. zoos have to keep animals in small cages

B. most animals in zoos are endangered species

C. some endangered animals are reproduced in zoos

D. it’s acceptable to keep animals away from their habitats

How would you like if you didn’t see me for two or three days?

Some years ago I was offered a writing assignment that would require three months of travel through Europe．I had been abroad a couple of times， 36 I could hardly claim to know my way around the continent．Moreover， my 37 of foreign languages was 38 to a little college French．
I 39 ．How would I，unable to speak the language and totally 40 with local geography or transportation systems， 41 interviews and do research? It seemed 42 ，and with much regret I sat down to write a letter begging 43 ．Halfway through，a thought ran through my mind：you can’t learn if you don’t 44 ．So I accepted the assignment.
There were some bad news. But by the time I had 45 the trip I was an experienced 46 ．And ever since，I have never hesitated to 47 for even the most remote places，without guides or even 48 bookings，confident that somehow I will 49 .
The point is that the new，the 50 ，is almost by definition scary．But each time you try 51 ，you learn，and as the learning piles up，the world 52 to you.
I’ve 53 to ski at 40，and flown up the Rhine River in a balloon．And I know I’ll go on doing such things．It’s not because I’m 54 or more daring than others. I’m not. But I’ll accept anxiety as another name for 55 and I believe I can accomplish wonders．

【小题5】A. occupied B. unfamiliar C: mixed D. popular

I recently heard a story about a famous scientist who had made several very important medical breakthroughs（突破）. He was being interviewed by a reporter who asked him    1   he thought he was able to be so much more    2   than the average person.
He responded that it all came from a(n)   3   with his mother that occurred when he was about 2. He had been trying to   4  milk from the fridge when he    5   the slippery(光滑的) bottle, its contents running all over the kitchen floor.
When his mother came in,    6   shouting at him or giving him a lecture, she said, “Robert, what a great and wonderful    7   you have made! I have    8   seen such a huge pool of milk. Well, the damage has already been    9  . Would you like to get down and    10   in the milk for a few minutes before we clean it up?”
Indeed, he did. After a few minutes, his mother said, “Robert, whenever you make a mess like this, eventually you have to restore everything to its proper order. So, how would you like to do that? We could use a sponge(海绵), a towel or a mop. Which do you prefer?” He chose the sponge.
His mother then said, “ You know, what we have here is a    11  experiment in how to effectively carry a big milk bottle with two    12   hands. Let’s go out in the back yard and fill the bottle with water and see if you can   13 .” The little boy learned that if he    14   the bottle at the top near the lip with both hands, he could carry it without dropping it. What a wonderful    15  !
This scientist then said that it was at that moment that he knew he didn’t need to be    16  to make mistakes. Instead, he learned that mistakes were just    17   for learning something new, which is,    18  , what scientific experiments are all about. Even if the experiment “doesn't   19 ,” we usually learn something    20   from it.

My wife passed away a few years ago, and I went through the worst time in my life. I even wanted to kill myself. Just for my kids, I had to continue to live and work as a small town doctor at my medical clinic in Hawaii. My kids had gone to live on the mainland, and I was alone. Then they asked me to have a family trip.
On our trip, we turned on the TV at the motel and saw the second plane crash into the World Trade Center. Seeing it falling down, I said to my kids：“ I'm going to Afghanistan.”And a few weeks later, International Medical Corps sent me to set up 20 clinics in provinces where people had no health care. In these field clinics surrounded by frightening shoots or deadly bombs ，we were eventually serving 27,000 patients a month in a very busy schedule.Tired and nervous, I gradually had a sense of achievement, a sense of purpose, and my depression went away.
In the years to follow, I went to Indonesia after the tsunami (海啸), Pakistan after the earthquakes, Sudan after the civil war, and Iraq after more and more bombs. Each time after disasters one after another, hundreds of people were killed, wounded and many more had to flee. We once set up movable clinics in an area with 19,000 refugees,_and it was supposed to hold 13,000 originally. Flu broke out, one of the biggest killers of kids in refugee camps, and it spread like wildfire. Water and food were also serious problems. “Adventure or not？”I often asked myself.
When my wife passed away, I thought my life was gone. But in reality, it was just getting started. At the end of her life, she went unconscious. I held her head in my hands and told her of all the places we would visit and the exciting adventures we would have.
I thought about the moment many times during my“adventures”. I didn't know how predictive those words would be，but I knew that she was still with me.
【小题1】Where has the doctor been in the past few years?

A．Some countries where he could set up clinics.

B．Some African countries where flu broke out.

C．The places where the earthquakes happened.

D．The places that the horrible disasters struck.

【小题2】How would the doctor describe his life after he had worked in Afghanistan?

A．Tired and troublesome.	B．Busy and risky.
C．Meaningful and helpful.	D．Frightening and depressing.

【小题3】The underlined word“ refugees” means people________.

A．who are robbed, killed, or wounded	B．who suffer from flu in movable clinics
C．who like to take adventures	D．who have lost homes because of disasters

【小题4】Which of the following is TRUE according to the passage?

A．The doctor's wife encouraged him to work in foreign countries.

B．What the doctor said to his wife before her death became reality.

C．The doctor's adventures made him understand the love of his wife.

D．With the true love of his wife, the doctor started to change his life.