Charles Darwin’s “On the Origin of Species” is credited with sparking evolution’s revolutionAin scientific thought, but many observers had pondered evolution before him. It was understood Bthe idea’s significance and selling it to the public that made Darwin great, according to the ArnoldC DArboretum’s new director.
相关问题推荐
-
One effect of the （ ）economy of 2009 on state and local governments is a decrease in income, sales, and property tax revenues.
A.prosperous B.sluggish C.substantial D.pervasive -
Engineering offers men and women an （ ）opportunity to experience the joy of improving the quality of life for humankind through development of engineering solutions to societal problems.
A.absolute B.unparalleled C.elaborate D.obsessive -
sleep="" alternation="" with="" some="" 16-17="" hours'="" wakefulness="" and="" that,="" broadly="" speaking,="" the="" normally="" coincides="" hours="" of="" darkness.="" our="" present="" concern="" is="" how="" easily="" to="" what="" extent="" this="" cycle="" can="" be="" modified. The question is no mere academic one. The ease, for example, with which people can change from working in the day to working at night, is a question of growing importance in industry where automation calls for round-the-clock working of machines. It normally takes from five days to one week for a person to adapt to reversed routine of sleep and wakefulness, sleeping during the day and working at night. Unfortunately, it is often the case in industry that shifts are changed every week; a person may work from 12 midnight to 8 a m one week, 8 a m to 4 p. m the next, and 4 p. in to 12 midnight the third and so on. This means that no sooner has he got used to one routine than he has to change to another, so that much of his time is spent neither working nor sleeping very efficiently. The only real solution appears to be to hand over the night shift to a number of permanent night workers. An interesting study of the domestic life and health of night-shift workers was carried out by Brown in 1957. She found a high incidence（发生率）of disturbed sleep and other disorders among those on alternating day and night shifts, but no abnormal occurrence of these phenomena among those on permanent night work. This latter system then appears to be the best long-term policy, but meanwhile something may be done to relieve the strains of alternate day and night work by selecting those people who can adapt most quickly to the changes of routine. One way of knowing when a person has adapted is by measuring his body temperature. People engaged in normal daytime work will have a high temperature during the hours of wakefulness and a low one at night; when they change to night work the pattern will only gradually go back to match the new routine and the speed with which it does so parallels, broadly speaking, the adaptation of the body as a whole, particularly in terms of performance. Therefore, by taking body temperature at intervals of two hours throughout the period of wakefulness it can be seen how quickly a person can adapt to a reversed routine, and this could be used as a basis for selection. So far, however, such a form of selection does not seem to have been applied in practice. 1.Why is the question of “how easily people can get used to working at night” not a mere academic question? 2.The main problem of the round-the-clock working system lies in （ ）. 3.The best solution for implementing the 24-hour working system seems to be （ ）. 4.It is possible to find out if a person has adapted to the changes of routine by measuring his body temperature because （ ）. 5.Which of the following statements is NOT TRUE?'>
We all know that the normal human daily cycle of activity is of some 7-8 hours' sleep alternation with some 16-17 hours' wakefulness and that, broadly speaking, the sleep normally coincides with the hours of darkness. Our present concern is with how easily and to what extent this cycle can be modified.The question is no mere academic one. The ease, for example, with which people can change from working in the day to working at night, is a question of growing importance in industry where automation calls for round-the-clock working of machines. It normally takes from five days to one week for a person to adapt to reversed routine of sleep and wakefulness, sleeping during the day and working at night. Unfortunately, it is often the case in industry that shifts are changed every week; a person may work from 12 midnight to 8 a m one week, 8 a m to 4 p. m the next, and 4 p. in to 12 midnight the third and so on. This means that no sooner has he got used to one routine than he has to change to another, so that much of his time is spent neither working nor sleeping very effic
-
With many ethnic groups represented, the student union is very （ ）.
A.homogeneous B.heterodox C.heterogeneous D.heterogeneousness -
At present rates of demand, the world has enough oil in known and economically viable reserves to last for more than 40 years, enough gas for more than 60 years and enough coal for more than 230 years. Naturally, demand will increase; but so will reserves as companies explore more widely and costs fall. Since 1970 viable reserves of oil have almost doubled while those of gas have leapt three-fold. One distant day a difficult situation will come, but as it approaches, fossil-fuel prices will rise, making alternative forms of energy, perhaps including nuclear power, competitive. That is no reason to spend on nuclear right now.All oil shock is a more worrying prospect despite today’s low oil price and OPEC’s present inability to budge it upwards. However, even if an oil shock is a real danger, building nuclear reactors is not a good way to avert it. A higher oil price would have a relatively small effect on the supply of electricity-the only sort of energy that nuclear power can now provide. Just over a tenth of the world’s electricity is generated from oil, and the proportion has steadily fallen since 1970. Transport, by contrast, relies almost entirely upon oil, already swallowing half the world’s oil supply and likely to take an even larger chunk in the future. If the supply of oil were cut off tomorrow, billions of people would find themselves immobile. Relatively few would be without electricity.The congestion and pollution are serious problems, and they could try to restrict the growth of car use, or promote cars which use less fuel. For governments keen to reduce electricity’s dependence on oil still further, there are usually cheaper alternatives to nuclear, such as coal or hydro power.Climate change is a legitimate worry. Although still riddled with uncertainties, the science of climate change is becoming firmer: put too much carbon in the atmosphere and you might end up cooking the earth, with possible catastrophic results. But here again switching immediately to nuclear power is not the best response. Cutting the larger subsidies that go to the world’s coal producers would help tilt the world’s energy balance towards natural gas, which gives off much less carbon dioxide. Developing countries subsidize electricity prices up to $120 billion a year, according to World Bank estimates. If price reflected the true costs of generation, electricity demand would fall, thus, cutting greenhouse emissions.1.What is the main idea of the first paragraph?2.Which of the following would NOT be true if an oil shock came soon?3.What is NOT mentioned as a way to prepare for an oil shock?4.What is meant by “cooking the earth”？5.What is the main aim of the passage?
A.Oil, gas and coal play an important role in energy supply. B.The more reserves, the greater demand there is for energy. C.There is no point in bothering about nuclear power at present. D.Some other forms of energy will replace fossil fuels someday.
问题2：
A.It wouldn’t affect much of the supply of electricity. B.It would have great impact on transport. C.The world would be badly in need of nuclear plants. D.Oil price would go upwards.
问题3：
A.Exploiting nuclear energy instead. B.Promoting cars which consume less fuel. C.Building up stock of oil for future consumption. D.Using coal or hydro power.
问题4：
A.The earth is getting wanner as if fueled by carbon dioxide dischargers. B.Owing to the change of climate, there will be less oil reserves C.The power plant emits too much smoke and fume. D.Automobile exhausts give off too much carbon dioxide.
问题5：
A.To reject the idea of turning to nuclear reactors for energy. B.To demonstrate that there are alternative forms of energy. C.To defend oil consumption from the blame for greenhouse effect. D.To warn people of the inevitable exhaustion of fossil fuels.