请输入或粘贴题目内容
搜题
拍照、语音搜题，请扫码下载APP
题目内容
（请给出正确答案）
(Leading) scientists are often the (kinds of person) who (have enjoyed) intellectual challenges (all their lives).
A．Leading
B．kinds of person
C．have enjoyed
D．all their lives
答案
更多“（Leading) scientists are often the （kinds of person) who （have enjoyed) intellectual chall”相关的问题
第1题
Scientists were embroiled (使卷入) last week in an international row over genetically modified cotton (GM cotton).
A study in China suggested for the first time that the crop was permanently damaging the environment and that insects were building up resistance to it.
The study, by the Nanjing institute of Environmental Science, combined the laboratory and field work from four Chinese scientific institutes. The study was done over a several - year period.
GM Cotton had a gene resistance to the cotton bollworm (棉铃虫) and isolated from the bacterium (细菌) named Bacillus thuringiensis (Bt), but the study found that it harms the natural parasitic (寄生的) enemies of the cotton bollworm.
It also indicated that populations of pests besides the bollworm had increased in Bt cotton fields and some had replaced the bollworm as the primary pest.
However, the leading GM company, the US's Monsanto, which controls more than 80 per cent of the Bt cotton grown worldwide, dismissed the research.
It said that the industry has always cited GM cotton as its biggest success, because it can increase yields by up to 60 per cent and reduce the need for pesticides (杀虫剂) by 80 per cent.
But, unfortunately for the industry, (80) the scientists also found that the resistance of Bt cotton to bollworm decreased significantly over time.
Why scientists say no to GM cotton？
A．Because the cotton was genetically modified.
B．Because the cotton was found to damage the environment.
C．Because the cotton harms the bollworm.
D．Because Monsanto dismissed the research.
第2题
A book to be published in Britain this week, The End of Science, argues persuasively that this is the case. Its author, John Horgan, is a senior writer for Scientific American magazine, who has interviewed many of today's leading scientists and science philosophers. The shock of realizing that science might be over came to him, he says, when he was talking to Oxford mathematician and physicist Sir Roger Penrose.
The End of Science provoked a wave of denunciation in the United States last year. "The reaction has been one of complete shock and disbelief, "Mr. Horgan says.
The real question is whether any remaining unsolved problems, of which there are plenty, lend themselves to universal solutions. If they do not, then the focus of scientific discovery is already narrowing. Since the triumphs of the 1960s—the genetic code, plate tectonics, and the microwave background radiation that went a long way towards proving the Big Bang—genuine scientific revolutions have been scarce. More scientists are now alive, spending more money on research, that ever. Yet most of the great discoveries of the 19th and 20th centuries were made before the appearance of state sponsorship, when the scientific enterprise was a fraction of its present size.
Were the scientists who made these discoveries brighter than today's？ That seems unlikely. A far more reasonable explanation is that fundamental science has already entered a period of diminished returns. "Look, don't get me wrong," says Mr Horgan. "There are lots of important things still to study, and applied science and engineering can go on for ever. I hope we get a cure for cancer, and for mental disease, though there are few real signs of progress."
The sentence "most of the best things have already been located" could mean______.
A．most of the best things have already been changed
B．most of the best things remain to be changed
C．there have never been so many best things waiting to be discovered
D．most secrets of the world have already been discovered
第3题
A study published recently in the journal Nature shows that air- borne leaded gas emissions from the United States were the leading contributor to the high concentration of lead in the snow in Greenland. The new study is a result of the continued research led by Dr. Charles Boutron, an expert on the impact of heavy metals on the environment at the National Center for Scientific Research in France. A study by Dr. Boutron published in 1991 showed that lead levels in arctic snow were declining.
In his new study, Dr. Boutron found the ratios of the different forms of lead in the leaded gasoline used in the United States were different from the ratios of European, Asian and Canadian gasoline and thus enabled scientists to differentiate the lead sources. The dominant lead ratio found in Greenland snow matched that found in gasoline from the United States.
In a study published in the. journal Ambio, scientists found that lead levels in soil in the North-eastern United States had decreased markedly since the introduction of unleaded gasoline.
Many scientists had believed that the lead would stay in soil and snow for a longer period.
The authors of the Ambio study examined samples of the upper layers of soil taken from the same sites of 30 forest floors in New England, New York and Pennsylvania in 1980 and in 1990.
The forest environment processed and redistributed the lead faster than the scientists had expected.
Scientists say both studies demonstrate that certain parts of the ecosystem respond rapidly to reductions in atmospheric pollution, but that these findings should not be used as a license to pollute.
1. Lead accumulation worldwide decreased significantly after the use of unleaded gas in the US .
A、 was discouraged
B、was enforced by law
C、was prohibited by law
D、 was introduced
2. It can be inferred from the last paragraph that scientists .
A、are puzzled by the mystery of forest pollution
B、feel relieved by the use of unleaded gasoline
C、still consider lead pollution a problem
D、lack sufficient means to combat lead pollution
第4题
Until now, a draft report currently circulating on the Internet asserts that the global temperature rise can now be blamed, at least in part, on human activity. Statements like this have been made before by individual researchers-who have been criticized for going too far beyond the scientific consensus. But this report comes from the International Panel on Climate Change (IPCC), a respected UN sponsored body made up of more than 1,300 leading climate experts from 40 nations. This shift in scientific consensus is based not so much on new data as on improvements in the complex computer models that climatologists use to test their theories. Unlike chemists or molecular biologists, climate experts have no way to do lab experiments on their specialty. So they simulate them on supercomputers and look at what happens when human generated gases-carbon dioxide from industry and auto exhaust, methane from agriculture, chlorofluoro carbons from leaky refrigerators and spray cans-are pumped into the models virtual atmospheres.
Until recently, the computer models weren't working very well. When the scientists tried to simulate what they believe has been happening over the past century or so, the results didn't mesh with reality; the models said the world should now he warmer than it actually is. The reason is that the computer models had been overlooking an important factor affecting global temperatures: sulfur dioxides that are produced along with CO2 when fossil fuels are burned in cars and power plants. Aerosols actually cool the planet by blocking sunlight and mask the effects of global warming. Once the scientists factored in aerosols, their models began looking more like the real world. The improved performance of the simulations was demonstrated in 1991, when they successfully predicted temperature changes in the aftermath of the massive Mount Pinatubo eruption in the Philippines. A number of studies since have added to the scientists confidence that they finally know what they are talking about-and can predict what may happen if greenhouse gases continue to be pumped into the atmosphere unchecked.
Gingrichian politicians reluctant to address the problem because______.
A．they think it is anything but a natural phenomenon
B．the efforts may turn to be too difficult and expensive
C．they think the predicted disaster is only hypothetical
D．some scientists have gone too far beyond the scientific consensus
第5题
With an in vitro culturing technique, researchers are deciphering how biochemical agents regulate the secretion of prolactin, the pituitary hormone that promotes milk production. The cultured cells survive for as long as a month, and they do not require serum, a commonly used culture ingredient that can influence cellular function and confound study results. One primate pituitary gland may yield enough cells for as many as 72 culture dishes, which otherwise would require as many animals.
The other technique allows scientists to monitor cellular differentiation in the reproductive tracts of female monkeys. While falling short of the long-sought goal of developing an in vitro model of the female reproductive system, the next-best alternative was achieved. The method involves transplanting oviduct tissue to an easily accessible site under the skin, where the grafted cells behave exactly as if they were in their normal environment. In about 80 percent of the grafts, blood vessels in surrounding abdominal skin grow into and begin nourishing the oviduct tissue. Otherwise, the tissue is largely isolated, walled off by the surrounding skin. A cyst forms that shrinks and swells in tandem with stages of the menstrual cycle. With about 80 percent of the grafts re-establishing themselves in the new site, a single monkey may bear as many as 20 miniature oviducts that are easily accessible for study. Because samples are removed with a simple procedure requiring only local anaesthesia, scientists can track changes in oviduct cells over short intervals. In contrast, repeated analysis of cellular changes within the oviduct itself would require abdominal surgery every time a sample was taken--a procedure that the animals could not tolerate.
Scientists are using the grafting technique to study chlamydia infections, a leading cause of infertility among women. By infecting oviduct tissues transplanted into the abdominal skin of rhesus monkeys, researchers hope to determine how the bacteria cause pelvic inflammatory disease and lesions that obstruct the oviduct. Such research could eventually lead to the development of antibodies to the infectious agent and a strategy for producing a chlamydia vaccine.
This passage deals primarily with ______.
A．reproductive organs of nonhuman primates
B．diseases of the pituitary glands
C．in vitro studies of pituitary hormones
D．techniques for studying hormonal reactions
第6题
Part A
Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D. (40 points)
The pollution of Hong Kong's beaches by oil from a damaged tanker last year recalls a similar incident which took place in Britain in 1967 when the Torrey Canyon, a huge oil tanker, split in two and caused disaster in coastal areas. Shoals of fishes were killed, sea birds hopelessly fouled with oil and coastal holiday resorts put out of business for several weeks. As a result of this particular incident scientists are becoming restless at the thought of Britain's inability to cope with national disasters on a large scale. The reason for their concern is that technology is rapidly outstripping(超越) man's ability to control it.
Oil tankers, for instance, have been allowed to get bigger and bigger without sufficient thought being given to emergency braking and maneuvering arrangement. Collisions at sea continue, but little effect has been made to develop safety devices as effective as those used for aircraft.
Scientists were outspoken in expressing their concern during a recent meeting of the British Association. Unanimous approval was voiced when the leading speaker urged that a permanent national rescue services should be established, equipped for any emergency and ready to move off immediately.
Of all the possible disasters mentioned, the one promoting most discussion was a major release of radioactivity from a nuclear power station. One does not need a particularly vivid imagination to visualize the other possibilities discussed. What would be the effect of a jumbo-jet crashing on a large chemical plant handling destroying liquids？ Could the tapping of natural gas lead to any form. of collapse？ Suppose a lorry full of a highly poisonous chemical crashed unseen into a large reservoir？ Dams can burst, abnormal conditions can lead to massive electrical blackouts.
An intensive study of such possibilities could at least reduce the effects of future disasters. For example, it would mean that a number of technical alternatives (such as the choice between detergent or chalk for dispersing oil) could be examined and tested in advance so that specially trained expert would know exactly what action was needed in a given emergency.
The main idea of the second paragraph is that ______.
A．safety precautions in aircraft are not as effective as those used on ships
B．modern oil tankers can stop or turn easily in spite of their size
C．there are now fewer collisions at sea because of modern safety devices
D．oil tankers are so big that special devices are needed
第7题
A leading cause of the【7】divorce rate (more than half of all marriages end in divorce) is the failure of husbands and wives to【8】effectively. They don't listen to each other. Neither person【9】to the actual message sent by the other.
In【10】fashion, political scientists report that a growing number of people believe that their elected and【11】officials are out of【12】with the constituents they are supposedly【13】Why？ Because they don't believe that they listen to them. In fact, it seems that sometimes our politicians don't even listen to themselves. The following is a true story: At a national【14】conference held in Albuquerque some years ago, then Senator Joseph Montoya was【15】a copy of a press release by a press aide shortly before he got up before the audience to【16】a speech. When he rose to speak,【17】the horror of the press aide and the【18】of his audience, Montoya began reading the press release, not his speech. He began, "For immediate release. Senator Joseph M. Montoya, Democrat of New Mexico, last night told the National... " Montoya read the entire six page release,【19】with the statement that he "was repeatedly【20】by applause. "
(1)
A．scarce
B．little
C．rare
D．poor
第8题
Humans have altered the world's climate by (1)_____ heat-trapping gases since almost the beginning of civilization and even prevented the start of an ice age several thousand years ago, a scientist said.
Most scientists (2)_____ a rise (3)_____ global temperatures over the past century (4)_____ to emissions of carbon dioxide (5)_____ human activities like driving cars and operating factories.
Dr. William Ruddiman, a professor at the University of Virginia, said at a meeting of the American Geophysical Union (6)_____ humans' effect (7)_____ climate went back nearly 10, 000 years (8)_____ people gave up hunting and gathering and began farming.
In a commentary accompanying the article, Dr. Thomas J. Crowley of Duke University, said he (9)_____ Dr. Ruddiman's premise at first. "But when I started reading, Dr. Crowley wrote, "I could not help but (10)_____ whether he just might be (11)_____ something."
The climate of the last 10,000 years has been unusually stable, (12)_____ civilization to flourish. But that is only because people chopped down swaths of forest in Europe, China and India for croplands and pastures. Carbon dioxide (13)_____ by the destruction of the forests, plus methane, another heat-trapping gas, (14)_____ by irrigated rice fields in Southeast Asia, trapped enough heat to (15)_____ an expected natural cooling.
Levels of carbon dioxide and methane rise and fall in natural cycles (16)_____ thousands of years, and both reached a peak at the end of the last ice age 11;000 years ago. Both then declined (17)_____ expected.
Both (18)_____ declining through the present day, leading to lower temperatures, and a new ice age should have begun 4,000 to 5,000 years ago, Dr. Ruddiman said. Instead, levels of carbon dioxide reversed 8,000 wears ago. The decline (19)_____ methane levels reversed 5,000 years ago, (20)_____ with the advent of irrigation rice farming.
A．generating
B．generated
C．originating
D．originated
第9题
Part A
Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D. (40 points)
Placing a human being behind the wheel of an automobile often has the same curious effect as cutting certain fibres in the brain.
The result in either case is more primitive behaviour. Hostile feelings are apt to be expressed in an aggressive way.
The same man who will step aside for a stranger at a doorway will, when behind the wheel, risk an accident trying to beat another motorist through an intersection. The importance of emotional factors in automobile accidents is gaining recognition. Doctors and other scientists have concluded that the highway death toll resembles an epidemic and should be investigated as such.
Dr. Ross A. McFarland, Associate Professor of Industrial Hygiene at the Harvard University School of Public Health, said that accidents “now constitute a greater threat to the safety of large segments of the population than diseases do. ”
Accidents are the leading cause of death between the ages of 1 and 35. About one third of all accidental deaths and one seventh of all accidental injuries are caused by motor vehicles.
Based on the present rate of vehicle registration, unless the accident rate is cut in half, one of every 10 persons in the country will be killed or injured in a traffic accident in the next 15 years.
Research to find the underlying causes of accidents and to develop ways to detect drivers who are apt to cause them is being conducted at universities and medical centres. Here are some of their findings so far:
A man drives as he lives. If he is often in trouble with collection agencies, the courts, and police, chances are he will have repeated automobile accidents. Accident repeaters usually are egocentric, exhibitionistic, resentful of authority, impulsive, and lacking in social responsibility. As group, they can be classified as borderline psychopathic personalities, according to Dr. McFarland.
The suspicion, however, that accident repeaters could be detected in advance by screening out persons with more hostile impulses is false. A study at the University of Colorado showed that there were just as many overly hostile persons among those who had no accidents as among those with repeated accidents.
Psychologists currently are studying Denver high school pupils to test the validity of this concept. They are making psychological evaluations of the pupils to see whether subsequent driving records will bear out their thesis.
The author believes that, behind the wheel of an automobile, some people act
A．as though they were uncivilized.
B．as though they should change their attitudes from hostility to amicability.
C．as though their brain fibres needed cutting.
D．as though they wanted to repress hostile feelings.
