Birds that are half-asleep—with one brain hemisphere (半球) alert and the other sleeping—control which side of the brain remains awake, according to a new study of sleeping ducks.
Earlier studies have documented half-brain sleep in a wide range of birds. The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves. The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert. Birds also can sleep with both hemispheres resting at once.
Decades of studies of bird groups led researchers to predict extra alertness in the end-of-the-row sleepers which tend to be attacked more easily. Sure enough, the end birds tended to watch carefully on the side away from their companions. Ducks in the inner spots showed no preference for gaze direction.
Also, birds napping at the end of the line depend on single-hemisphere sleep, rather than total relaxation, more often than inner ducks did. Turning 16 birds through the positions in a four-duck row, the researchers found that compared with 12 percent for birds in internal spots, outer birds half-asleep during some 32 percent of napping time.
“We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness at the same time in different regions of the brain,” the researchers say.
The results provide the best evidence for a long-standing assumption that single-hemisphere sleep evolved as creatures scanned for enemies. The preference for opening an eye on the lookout side could be widespread, he predicts. He’s seen it in a pair of birds napping side-by-side in the zoo and in a single pet bird sleeping by a mirror. The mirror-side eye closed as if the reflection were a companion and the other eye stayed open.
Useful as half-sleeping might be, it’s only been found in birds and such water animals as dolphins, whales, and seals. Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning.
Studies of birds may offer unique insights into sleep. Jerome M. Siegel of the UCLA says he wonders if birds’ half-brain sleep “is just the tip of the iceberg.” He supposes that more examples may turn up when we take a closer look at other species.
72. According to the passage, birds often half sleep because ______.
A. they have to watch out for possible attacks
B. their brain hemispheres take turns to rest
C. the two halves of their brain are differently structured
D. they have to constantly keep an eye on their companions
73. What is implied about the example of a bird’s sleeping in front of a mirror?
A. An imagined companion gives the bird a sense of security.
B. Birds prefer to sleep in pairs for the sake of their security.
C. The phenomenon of birds napping in pairs is widespread.
D. A single pet bird enjoys seeing its own reflection in the mirror.
74. While sleeping, some water animals tend to keep half awake in order to ______.
A. alert themselves to the approaching enemy
B. emerge from water now and then to breathe
C. be sensitive to the ever-changing environment
D. avoid being swept away by rapid currents
75. By saying “just the tip of the iceberg”, Siegel suggests that ______.
A. half-brain sleep has something to do with icy weather
B. the mystery of half-brain sleep is close to being solved
C. most birds living in cold regions tend to be half sleepers
D. half-brain sleep may exist among other species
.
If there is something that appears most frequently on Chinese dining tables, it is beancurd（豆腐）. Beancurd looks like soft cakes and it’s made from dried soybeans. Beancurd used to be considered a favourite of the poor because of its low cost. Beans have high yields (产量) every year with their short growing period and suitability for various (各种各样) soil both dry and wet.
Historical records show beancurd was invented by Liu An, Prince of Huainan and uncle of Emperor Wu of Han Dynasty（206BC—220AD）. He had a dream of finding the pill for longevity (长寿). He traveled all over the country and found soybeans, which looked much the same as gold in terms of colour. He collected soybeans, put them in the water and crushed them into pulp (浆). It got solidified and became known as doufu. Although it’s not able to keep longevity, it’s really good for one’s health with high protein and low fat.
With a long history, beancurd is rooted deep in Chinese culture. People eat more meat and fish than beancurd. But they are encouraged to have beancurd every once in a while for it’s really good for health. Most Chinese people still keep beancurd as one of their favourite dishes.
64. Why was beancurd considered to be liked by the poor?
A. It’s easy to make. B. It’s easy to cook. C. It’s cheap. D. It’s good for health.
65. Where can beans grow well?
A. Only in wet soil. B. In dry soil. C. In soft soil. D. In any soil.
66. Why did Liu An travel all over the country?
A. He had a dream.
B. He wanted to find something that could make people live longer.
C. He wanted to invent beancurd.
D. He wanted to find gold.
67. How long has beancurd been invented?
A. It’s about 1 700 years.
B. It’s less than 2 000 years.
C. It’s 500 years.
D. It’s more than 2 000 years.
.
The Internet has become part of teenager life.
A new report on 3,375 students aged from 10 to 18 in seven Chinese cities found that 38 percent of them believe they use the Internet often.
While most of them get useful information and use the Internet to help in their studies, some are not using it in a good way.
In order to help young people use the Internet in a good way, a textbook on good Internet behavior(行为) has started to be used in some Shanghai middle schools this term. The book uses real examples to teach students all about good ways of using the Internet. The book gives useful advice such as it is good to read news or find helpful information to study.
Some students also make online friends. But if you are meeting a friend offline, make sure your parents know. Teachers and parents all think the book is of great help. A teacher said the book would be a guide for teens using the Internet. She believes it will keep students away from bad sites. “Many students are using the Internet without guidance from their parents,” she said. “The book will teach students how to be a good person in the online world.”
60. The textbook mainly tells us ____.
A. why we should use the Internet B. how to study using the Internet
C. how to use Internet correctly D. how to get help from others
61. What’s the attitude(态度) of teachers and parents towards the textbook?
A. They are against it. B. They are for（支持） it.
C. The passage doesn’t mention. D. They don’t care about it.
62. According to the passage, teenagers are NOT encouraged to ____.
A. read online news
B. go online
C. find helpful information online
D. meet a friend offline without letting their parents know
63. From this passage we know that ____.
A. more and more students have given up visiting bad Web sites
B. schools and teachers begin to pay attention to students’ use of the Internet.
C. no more homework will be given in Shanghai middle schools
D. less and less information can be found on line
.
第三部分：阅读理解（共20小题，每小题2分；满分40分）
Sweetest Day is celebrated on the third Saturday in October as a day to make someone happy. It is an occasion which offers all of us an opportunity to remember not only the sick, the aged, and children who have lost their parents, but also friends, workmates, relatives and neighbors whose helpfulness and kindness we have enjoyed.
Over 60 years ago, when a Cleveland man noticed that some people, such as children who lost their parents and patients who lay in bed, too often felt forgotten and neglected, he developed in his mind the idea of showing them that they were remembered. He did this by giving them small gifts. With the help of his friends and neighbors, he gave those people small gifts on a Saturday in October. During the years that followed, other Clevelanders began to take part in the celebration, which came to be called “Sweetest Day”. Over time, the Sweetest Day idea of spreading cheer to the poor, the sick and children who had lost their parents was broadened to include everyone, and became an occasion for remembering others with a kind act or a small gift. Soon the idea spread to other cities all over the USA.
Sweetest Day is not based on any single group’s religious beliefs or on a family relationship. It is a reminder that a thoughtful word or deed enriches life and gives it meaning. Because for many people remembering takes the form of gift giving, Sweetest Day offers us the opportunity to show others that we care, in a positive （积极的） way.
56. What can we learn from the first paragraph?
A. Sweetest Day is a day to make others happy.
B. Sweetest Day is just an occasion to care about disabled people.
C. Sweetest Day is an occasion for lovers to express love.
D. Sweetest Day is celebrated on the third Sunday in October.
57. Which of the following has little relationship to Sweetest Day?
A. Visiting sick people of the hospital.
B. Visiting children who have lost the
ir parents.
C. Giving friends small gifts.
D. Giving flowers to sweethearts.
58. What do most people usually do to show their care to others according to the passage?
A. They give money. B. They give gifts.
C. They send regards. D. They offer help.
59. The underlined word “neglected” in the second paragraph means “______”.
A. remembered B. hated
C. paid little or no attention to D. disappointed
.
A new study suggests that the more teenagers watch television, the more likely they are to develop depression.
The researchers used a national long-term survey of teenagers’ health to investigate the relationship between media use and depression. They based their findings on more than four thousand teenagers who were not depressed when the survey began in nineteen ninety-five.
As part of the survey, the young people were asked how many hours of television or videos they watched daily. They were also asked how often they played computer games and listened to the radio.
Media use totaled an average of five and one-half hours a day. More than two hours of that was spent watching TV.
Seven years later, in two thousand two, more than seven percent of the young people had signs of depression. The average age at that time was twenty-one.
Brian Primack at the University of Pittsburgh medical school was the lead author of the new study. He says every extra hour of television meant an eight percent increase in the chances of developing signs of depression.
The researchers say they did not find any such relationship with the use of other media such as movies, video games or radio. But the study did find that young men were more likely than young women to develop depression.
The study was just published in the Archives of General Psychiatry this Monday. In December, the magazine Social Indicators Research published a study of activities that help lead to happy lives. They found that people who describe themselves as happy spend less time watching television than unhappy people. The study found that happy people are more likely to be socially active.
72. How many years has the mentioned survey lasted till 2009?
A. 7 B. 21 C. 14 D. 19
73. Which of the following is NOT true according to the passage?
A. Young women were less likely than young men to develop depression.
B. Happy people spend more time in watching TV.
C. Playing computers has nothing to do with the depression.
D. Teenagers spend about five and a half hours a day on media use.
74. The topic the author wanted to express through the passage is____.
A. Teens, television and depression B. Teens, media and depression
C. adults, television and happiness D. women , media and happiness
75. It can be inferred from the passage that________.
A. teenagers should be prevented from using media
B. depression is increasing at a speed of 8% a year
C. watching TV is part of teenagers’daily life
D. TV has ill effect on social life
.
Larry Walters’boyhood dream was to fly. After finishing school, Larry joined the U.S. Air Force, but was refused from pilot-training school because of poor eyesight. However, his dream remained.
Larry, aged 33, was a truck driver in Los Angeles. One day, while sitting outside and watching jets fly overhead, an idea came to him to use weather balloons to fly.
A few weeks later, Larry bought 42 weather balloons. He tied them to a chair and filled them with helium(氦). Then he sat down in the chair with some beer, sandwiches and a BB gun. Larry’s plan was to float about 10 meters above his backyard, enjoy a few hours in the air, and then pop some balloons with his gun to get back down. But things did not go according to Larry’s plan.
When his friends cut the lines, Larry lifted by the 42 balloons and shot skyward at an astonishing speed. He finally settled at an altitude of 4,000 meters. Afraid to pop any of the balloons, in case he should break the balance of his “craft”, Larry sat, cold and frightened, in the sky for 14 hours.
Airline pilots heading toward Los Angeles’busy international airport radioed in reports of the strange sight. Larry’s presence in the sky caused numerous planes to change their routes. Eventually, Larry worked up the nerve to shoot a few balloons and landed in power lines. Uninjured, he climbed down to safety and was arrested by waiting police.
Larry set a record for a gas-filled balloon flight. But it cost him. He was later fined $1,500 for breaking air safety regulations.
68. What’s the BB gun used for in the passage?
A. To protect Larry from unexpected danger. B. To fill the balloons with gas.
C. To shoot the balloons to get him back. D. To fight with the waiting police.
69. It turned out that Larry________.
A. floated about 10 meters high B. remained in the sky for 14 hours
C. set a world record in making balloons D. became a truck driver after the flight
70. The underlined part in Paragraph 5 most probably means ____.
A. watched carefully B. gathered his courage
C. kept his balance D. climbed down
71. It can be learned from the passage that________.
A. Larry’s boyhood dream came true in the end
B. Larry’s disappearance in the sky caused much trouble
C. Larry won a prize of $1,500 for his bravery
D. Larry was not accepted as a pilot for his poor hearing
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