In the 1980s, scientists around the world began to notice something strange: Frogs were disappearing. More recent research has shown that many kinds of amphibians (两栖动物) are declining or have become extinct. They have been around for a long time - over 350 million years. Why are they dying out now?

     Scientists are seriously concerned about this question. First of all, amphibians are an important source of scientific and medical knowledge. By studying amphibians, scientists have learned about new substances that could be very useful for treating human diseases. Further research could lead to many more discoveries, but that will be impossible if the amphibians disappear.

     The most serious aspect of amphibian loss, however, goes beyond the amphibians themselves. Scientists are beginning to think about what amphibian decline means for the planet as a whole. If the earth is becoming unlivable for amphibians, is it also becoming unlivable for other kinds of animals and human beings as well?

     Scientists now believe that amphibian decline is due to several environmental factors. One of these factors is the destruction of habitat, the natural area where an animal lives. Amphibians are very sensitive to changes in their habitat. If they cannot find the right conditions, they will not lay their eggs. These days, as wild areas are covered with houses, roads, farms, or factories, many kinds of amphibians are no longer laying eggs. For example, the arroyo toad (蟾蜍) of southern California will only lay its eggs on the sandy bottom of a slow-moving stream. There are very few streams left in southern California, and those streams are often muddy because of building projects. Not surprisingly, the arroyo toad is now in danger of extinction.

     There are a number of other factors in amphibian decline. Pollution is one of them. In many industrial areas, air pollution has poisoned the rain, which then falls on ponds and kills the frogs and toads that live there. In farming areas, the heavy use of chemicals on crops has also killed off amphibians. Another factor is that air pollution has led to increased levels of ultraviolet (UV) light. This endangers amphibians, which seem to be especially sensitive to UV light. And finally, scientists have discovered a new disease that seems to be killing many species of amphibians in different parts of the world.

     All these reasons for the disappearance of amphibians are also good reasons for more general concern. The destruction of land, the pollution of the air and the water, the changes in our atmosphere, the spread of diseases - these factors affect human beings, too. Amphibians are especially sensitive to environmental change. Perhaps they are like the canary (金丝雀) bird that coal miners once used to take down into the mines to detect poisonous gases. When the canary became ill or died, the miners knew that dangerous gases were near and their own lives were in danger.

 

36 Losing amphibians means losing

     A　knowledge about fatal human diseases.

     B　knowledge about air and water pollution.

     C　a chance to discover new medicines.

D　an opportunity to detect poisonous gases.

 

37 Amphibians lay their eggs

     A　in any stream they can find,

     B　in places without UV light,

     C　only on sand.

D　only in the right conditions

 

38 The arroyo toad is disappearing because

     A　it has been threatened by frogs.

     B　it is losing its habitat.

     C　a disease has been killing its eggs.

D　it can't bear the cold of winter.

 

39 Coal miners once used the canary bird to detect

     A　poisonous gases.

     B　air pollution.

     C　water leakage.

D　radiation.

 

40 Scientists think that the decline of amphibians could

     A　cause environmental change.

     B　cause a decline in other kinds of animals.

     C　be a warning signal for human beings.

     D　be a good sign for human beings.

 

 

     Belle, our tiny monkey, was seated in her special chair inside a chamber at our Duke University lab. Her right hand grasped a joystick (操纵杆) as she watched a horizontal series of lights on a display panel. She knew that if a light suddenly shone and she moved the joystick left or right to correspond to its position, she would be sent a drop of fruit juice into her mouth.

     Belle wore a cap glued to her head. Under it were four plastic connectors, which fed arrays of microwires-each wire finer than the finest sewing thread- into different regions of Belle's motor cortex (脑皮层), tile brain tissue that plans movements and sends instructions. Each of the 100 microwires lay beside a single motor neuron (神经元). When a neuron produced an electrical discharge, the adjacent microwire would capture the current and send it up through a small wiring bundle that ran from Belle's cap to a box of electronics on a table next to the booth. The box, in turn, was linked to two computers, one next door and the other half a country away.

     After months of hard work, we were about to test the idea that we could reliably

translate the raw electrical activity in a living being's brain-Belle's mere thoughts-into signals that could direct the actions of a robot. We had assembled a multijointed robot arm in this room, away from Belle's view, which she would control for the first time. As soon as Belle's brain sensed a lit spot on the panel, electronics in the box running two real-time mathematical models would rapidly analyze the tiny action potentials produced by her brain cells. Our lab computer would convert the electrical patterns into instructions that would direct the robot arm. Six hundred miles north, in Cambridge, Mass, a different computer would produce the same actions in another robot arm built by Mandayam A. Srinivasan. If we had done everything correctly, the two robot arms would behave as Belle's arm did, at exactly the same time.

     Finally the moment came. We randomly switched on lights in front of Belle, and she immediately moved her joystick back and forth to correspond to them. Our robot arm moved similarly to Belle's real arm. So did Sriniwlsan's. Belle and the robots moved in synchrony (同步), like dancers choreographed (设计舞蹈动作) by the electrical impulses sparking in Belle's mind.

     In the two years since that day, our labs and several others have advanced neuroscience, computer science and microelectronics to create ways for rats, monkeys and eventually humans to control mechanical and electronic machines purely by "thinking through," or imagining, the motions. Our immediate goal is to help a person who has been unable to move by a neurological (神经的) disorder or spinal cord (脊髓) injury, but whose motor codex is spared, to operate a wheelchair or a robotic limb.

 

41　Belle would be fed some fruit juice if she

     A　grasped the joystick.

     B　moved the joystick to the side of the light.

     C　sat quietly in a special chair.

D　watched lights on a display panel.

 

42 The wires fixed under Belle's cap were connected to

     A　a plastic box next door.

     B　a computer at Cambridge University,

     C　a box of electronics in the booth.

D　a box which, in turn, was linked to two computers

 

43 Which of the following is NOT true of the robot built by Srinivasan?

     A　It was directed by signals converted from the electrical activity in Belle's brain

     B　It converted the electrical patterns into instructions for the other robot.

     C　It was six hundred miles away from where Belle was.

D　It could perform the same function as Belle did.

 

44 Which of the following statements indicates the success of the experiment?

     A　Belle responded to the robots successfully.

     B　Belle and the robots danced beautifully.

     C　Belle and the robots responded to the lights at the same time.

D　The two robots moved the joysticks successively.

 

45 The short-term goal of the research is to help a person

     A　whose motor cortex is seriously damaged.

     B　who can operate a wheelchair but not a robotic limb.

     C　who has spinal cord injury but is able to move a wheelchair.

     D　who is unable to move but whose motor cortex is not damaged

 

第5部分：补全短文（第46～50题，每题2分，共10分）

下面的短文有5处空白，短文后有6个句子，其中5个取自短文，请根据短文内容将其分别放回原有位置，以恢复文章原貌。

 

     African-American talk show queen Oprah Winfrey is the world's most powerful celebrity, according to Forbes magazine. 　　　　　 (46)

     Winfrey, 51, draws 30 million viewers weekly in the United States. Her talk show reaches 112 countries. She earned US$225 million over the past 12 months to rank second in celebrity riches.

The annual Forbes list gives most weight to annual earnings. 　　　　　(47)

     "After 21 years, her exciting chat show still rules the airwaves. It created new celebrities and hundreds of millions of dollars in profits," the magazine said.

     Winfrey is most popular with her popular talk show "The Oprah Winfrey Show". She can always attract the superstars and let them open up to her intimate interviewing style.

     Last month, American actor Tom Cruise, 42, surprised fans when he celebrated his new romance with 26-year-old actress Katie Holmes. He jumped up and down, shouting "I'm in love." Only a few years ago, Cruise and his ex-wife Nicole Kidman appeared separately on the same show telling the news of their divorce 　　　　　(48)

     Winfrey's approach appears to be simple. She is in pursuit of self-improvement and self-empowerment (自强). This has proved to be just what people, especially women, want.

     Winfrey often talks about her personal secrets on her show. That pulls in viewers. For example, she revealed that she had been sexually abused as a child, and has spoken freely of her struggle with her weight.

Winfrey was born to a poor family in Mississippi in 1954 　　　　　(49) At the age of 19, she became the youngest person and the first African*American woman to anchor (主持) a news programme.

     Her success has not just been on the screen. Her media group includes a women's TV network and websites for women.y

Winfrey's work has extended to social change. 　　　　　(50)

She testified before the US Senate to establish a national database of dangerous child abusers. President Bill Clinton later signed "Oprah Bill" into law.

 

A　But it also looks at the celebrity's presence on the Internet and in the media

B　In 1991, she did a lot of work for the National Child Protection Act.

C　She was not a very successful woman

D　She began broadcasting while still at high school

E　It placed Winfrey at the top of its annual ranking of the 100 people last week.

F　The couple had been tight-lipped about their break-up.

 

第6部分：完形填空（第51～65题，每题1分，共15分）

下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。

 

 

At the end of October 2003, a sudden solar storm hit the earth. A solar storm refers to the large amounts of charged particles released into space　　　　　(51) the solar energy increases. The release of the energy　　　　　 (52) place along with the activity of the sunspots with a cycle of: 11 years. This time, the          (53) of the storm exceeded expectations.

This　　　　　(54) of intense solar storm was caused by the eruption of a solar flare (闪光) and the ejection (喷发) of the solar corona (日冠) on October 28, 2003. Large amounts of charged particles moved 150,000,000 kilometers through space toward the 　　　　　(55) in 19 hours. They could affect aircraft roaming (漫游) in space.

The high-energy particles will　　　　　(56) some of the parts of an aircraft. They may also cause it to fail. High-energy particles can threaten the safety of an aircraft at a high orbit. If an aircraft orbits at a lower orbit, it is　　　　　(57) because it is under the protection of the earth's magnetic field.

 

　　A solar storm not only affects aircraft but also is a 　　　　　(58) to the environment and humans. The aerosphere and magnetic field of the earth can　　　　　(59) humans from ultraviolet radiation and X-rays. While most of the X-rays

are absorbed after they enter the aerosphere (大气层), still a few can　　　　　(60) the ground.

The geomagnetic storm caused by this round of solar storm reaches its highest level on the two　　　　　(61) of the earth, which affects electricity supply of North America. Overexposure to　　　　　(62) threatens the health of passengers on planes flying over the Polar Regions. If we fly in the sky during such a solar storm, it　　　　　(63) we receive ten times the X-ray radiation. It's really damaging.

Scientists say a solar eruption is like the sun sneezing, which will make the earth　　　　　(64) a cold. Though this natural force is irresistible, scientists can still　　　　　(65) its movement accurately by monitoring. Facing successive solar storms, humans can't drop their guard

 

51 A since        B when        C until         D though

52 A finds        B adjusts     C holds         D takes

53 A intensity    B height      C width         D density

54 A piece        B part        C round         D set

55 A star         B earth       C moon          D sun

56 A dominate     B develop     C damage        D descend

57 A safe         B dangerous   C comfortable   D manageable

58 A limit        B cause       C force         D threat

59 A separate     B benefit     C distinguish   D protect

60 A lose         B reach       C break         D prepare

61 A poles        B mountains   C rivers        D lakes

62 A light        B storm       C radiation     D pressure

63 A recommends   B means       C proposes      D advises

64 A turn         B stop        C become        D catch

65 A detect       B start       C experience    D change

 

 

 

1	D	2	C	3	A	4	B	5	D
6	C	7	B	8	C	9	A	10	C
11	B	12	D	13	C	14	C	15	B
16	A	17	A	18	C	19	B	20	A
21	B	22	C	23	D	24	E	25	A
26	F	27	B	28	F	29	C	30	E
31	D	32	D	33	C	34	B	35	A
36	C	37	D	38	B	39	A	40	C
41	B	42	D	43	B	44	C	45	D
46	E	47	A	48	F	49	D	50	B
51	B	52	D	53	A	54	C	55	B
56	C	57	A	58	D	59	D	60	B
61	A	62	C	63	B	64	D	65	A

其中：

1－30每题1分；

31－45每题3分；

46－50每题2分；

51－65每题1分。

试卷总分：100分。

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