题目
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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
答案
解析
核心考点
试题【Birds that are half-asleep—with one brain hemisphere (半球) alert and the other sl】;主要考察你对题材分类等知识点的理解。[详细]
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阅读下面一段文章,从A 、B、 C、 D 四个选项中选出最佳选项。
Water costs money. In some places water is hard 36 . what 37 when a town has these problems ? A small town in California found a happy 38 .
Very 39 rain ever fell there. The town had no water 40 . The water it used was
41 from a river 300 miles away. As more people 42 live in the town, 43 water was needed. Now water 44 to be brought in from 600 miles ways. All these cost 45 money.
The town 46 a plan. It found 47 to clean its “dirty” water. Once the cleaned water was reused 48 many ways. Five 49 lakes was built. Here people could swim and fish and go 50 . They 51 have picnics in their new parks. Farmers had more water
52 their crops. New factories can be built, now that they have the promise of 53 .
In most places, water is used and thrown 54 . The town that saved 55 water has saved the town!
36. A. supplying B. getting C. to get D. to supply
37. A. happens B. happening C. is happened D. happened
38. A. key B. answer C. answering D. way
39. A. little B. a little C. few D. a few
40. A. of itself B. of its own C. for its own D. for itself
41. A. fetch B. take C. brought in D. guided
42. A. come to B. came to C. coming to D. came for
43. A. many B. plenty of C. more D. many more
44. A. has B. had C. must D. needed
45. A. many B. a few C. a great many D. a lot of
46. A. put B. made C. supply D. noticed
47. A. a way B. ways C. an answer D. a key
48. A. for B. by C. at D. in
49. A. man-making B. man-make C. man-made D. man made
50.A. boating B. to boat C. to boating D. on boating
51. A. must B. could C. needed D. had to
52. A. as B. with C. for D. to
53. A. water enough B. enough water C. crops enough D. enough crops
54. A. off B. of C. away D. out of
55. A. it’s B. its C. one’s D. his
The exciting life of the American aviation (航空)pioneer is dramatized in the movie Amelia, which is due to come out on October 23.
After Earhart paid a pilot $1 to take her up for a short fly in his plane, aviation became her love and career.
As she later explained, “Never do things others can do and will do, if there are things others cannot do or will not do.”
Earhart found herself a flying teacher and started to learn to fly. She took all sorts of jobs to pay for the lessons and to buy a second-hand plane on her 24th birthday.
In 1932, Earhart flew solo across the Atlantic. She became the first woman to make the solo crossing. She also made a flying suit for women and went on to design other clothes for women who led active lives. “Now and then women should do for themselves what men have already done —— occasionally what men have not done ——thereby establishing themselves as persons, and perhaps encouraging other women toward greater independence of thought and action.” she said.
When she was nearly 40, Earhart was ready for a final challenge—to be the first woman to fly around the world. However, in mid-flight, she and her navigator (导航员) disappeared in bad weather.
Earhart will be forever remembered as a brave pioneer for both aviation and for women.
59. According to the passage, which of the following statements is true?
A. A movie about Earhart’s exciting life has come out.
B. Earhart never did things others could and would do.
C. Earhart’s love for aviation came after she flew a plane for a short time.
D. In Earhart"s opinion, women should think and act more independently.
60. The underlined word in paragraph 2 means ____.
A. presented B. adopted C. published D. created
61. From the passage we can know that ____.
A. Earhart showed most interest in adventure trips to the Missouri River during her
childhood
B. Earhart s ambition was to fly across the Atlantic
C. Earhart challenged herself constantly
D. Besides flying, Earhart also designed planes and clothes
62. You can probably find this article in .
A. a booklet B. a newspaper C. a guide book D. an advertisement
According to Wu Zhenyun, a professor from the Psychological Research Institute under the Chinese Academy of Sciences, a person’s willingness to look in the mirror can reflect his or her mentality. When people don’t care too much about their age, they will try to carry themselves with ease and natural poise (姿态). They don’t mind looking in the mirror to see their own faces. Some people even love to look in the mirror from time to time to see whether they keep a good appearance. In this way, mirror becomes their best friend that help them to look confident.
On the other hand, some people are afraid of being old. They don’t want to see the wrinkles on their face and their hair turning grey. So they don’t want to look in the mirror. This actually reflects a negative attitude they hold towards life. In the long term, they might suffer from psychological pressure or some sort of depression, which is actually not a wise act.
“ Everyone can make themselves look charming at every age stage. If one is confident, one will always look beautiful, it shows that they accept themselves.” professor Wu said.
Mirror cannot only give confidence to one. By looking in the mirror, one can even find the traces of some diseases from one’s own face.
67.Why does the mirror become the best friend for some people?
A. Because it brings much confidence to them.
B. Because it makes them more beautiful.
C. Because it tells whether they are clean or not.
D. Because it helps them find their own faults.
68.The fact that some people are afraid of looking in the mirror reflects that______.
A. they suffer from metal disease B. they treat life in a negative way
C. they are too ugly D. they can’t bear the pressure of being old
69. The text tells us that______.
A. if you are willing to look in the mirror you are getting old
B. everyone can become attractive at any age
C. confidence can make a person look beautiful
D. old people will accept the reality when they are old
70. The writer wrote this passage to______.
A. advise people to look in the mirror constantly
B. reflect different attitude towards looking into a mirror
C. introduce a way of finding signs of disease from one’s face
D. analyze why people like and dislike to look in the mirror
E
Windows not only let light in to cut down an electricity use for lighting, but the light coming through the window also provides heat. However, windows are not something people typically associate with being a cutting edge technology. Researchers are now working on new technologies that enable a window to quickly change from clear to dark and anywhere in between with a turn of a switch.
“It took us a long time to figure out what a window really is,” says Claes Granqvist, a professor of solid—state physics at Uppsala University in Sweden.“It’s contact with the outside world. You have to have visual contact with the surrounding world to feel well.” So, windows and natural light are important for improving the way people feel when they’re stuck indoors.
Yet, windows are the weak link in a building when it comes to energy and temperature control. In the winter, cold air leaks in. When it’s hot and sunny, sunlight streams in. All of this sunlight carries lots of heat and energy. And all of this extra heat forces people to turn on their air conditioners. Producing cold air, which can feel so refreshing, actually suck up enormous amounts of electricity in buildings around the world.
Windows have been a major focus of energy research for a long time. Over the years, scientists have come up with a variety of strategies for coating, glazing, and layering windows to make them more energy efficient. Smart windows go a step further. They use some technologies involving changes of color.
Electrochromic windows use electricity to change color. For example, a sheet of glass coated with thin layers(层) of tungsten oxide(氧化钨) works a bit like a battery. Tungsten oxide is clear when an electric charge is applied and dark when the charge is removed, that is, when the amount of voltage(电压) is decreased, the window darkens until it’s completely dark after all electricity is taken away. So applying a voltage determines whether the window looks clear or dark.
One important feature that makes a smart window so smart is that it has a sort of “memory”. All it takes is a small shock of voltage to turn the window from one state to the other. Then, it stays that way. Transitions take from 10 seconds to a few minutes, depending on the size of the window. The development of smart windows could mean that massive air conditioning systems may no longer need.“In the future,” Granqvist says,“our buildings may look different.”
67.Which statement does not indicate the importance of windows as described in the first two paragraphs?
A.Windows can change from clear to dark to save energy.
B.Windows help to save energy by letting light in.
C.Windows help to save energy by providing heat.
D.Windows enable people to have contact with the outside world.
68.According to the passage, smart windows are windows_______.
A.that are coated B.that use electricity
C.the color of which can be changed D.that have many layers
69.To make electrochromic windows change color, what is applied to the window glass?
A.Electricity. B.Tungsten oxide. C.A battery. D.A voltage.
70.What will be the benefit if the research on smart windows turns out to be successful?
A.The buildings will look different.
B.Windows can be as large as you want.
C.We may not need air conditioners any more.
D.They are less expensive than traditional windows.
Long ago, operation had usually to be done while the sick man could feel everything. The sick man had to be held down on a table by force while the doctors did their best for him. He could feel all the pain if his leg or arm was being cut off, and his fearful cries filled the room and the hearts of those who watched.
Soon after 1770, Josept Priestley discovered a gas which is now called “laughing gas”.Laughing gas became known in America.Young men and women went to parties to try it. Most of them spent their time laughing,but one man at a party,Horace Wells,noticed that people didn"t seem to feel pain when they were using this gas.He decided to make an experiment on himself.He asked a friend to help him.
Wells took some of the gas,and his friend pulled out one of Well’s teeth.Wells felt no pain at all.
As he didn"t know enough about laughing gas, he gave a man less gas than he should have. The man cried out with pain when his tooth was being pulled out.
Wells tried again,but this time he gave too much of the gas,and the man died.Wells never forgot this terrible event.
56.It is ___________since a man being operated felt all the pain.
A.a few more years B.not long C.few years D.two thousand years
57. Long ago, when the sick man was operated on, he___________.
A.could feel nothing B.could not want anything
C.could feel all the pain D.could do anything
58.Using the laughing gas, the people did not seem to___________.
A.be afraid of anything B.feel pain C.want to go to the parties D.be ill
59.If a man took less laughing gas than he should have when an operation went on he___________.
A.felt nothing B.felt very comfortable C.still felt pain D.would die
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