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Have you seen Jurassic Park? In this film, scientists use DNA kept for tens of millions of years to clone dinosaurs. They find trouble, however, when they realize that the cloned creatures are smarter and more erous than expected. That’s nothing more than a fiction. But could we really clone enered animals? To date, the most successful att empt to do so was the cloning of a gaur, a rare ox-like animal from southeast Asia. Scientists used a cow to bring the cloned baby gaur, named Noah. Two days after birth, however, Noah died from a common bacterial infection. Other enered species that may be cloned include the African bongo antelope (邦戈羚羊), the Sumatran tiger, the cheetah (猎豹), and the giant panda.     Next, could we really clone extinct animals? In theory? Yes. To do this, you need a well-kept source of DNA from the extinct animals such as wool mammoth (毛象), Tasmanian tiger, or even dinosaur, and a closely related species, still living, which could serve as a surrogate mother. In reality? Probably not. On the one hand, it’s not likely that extinct animals’ DNA could survive undamaged for such a long time. Cloning extinct animals as wool mammoth, Tasmanian tiger, or dinosaur is much more difficult due to the lack of properly well-preserved DNA. On the other hand, for example, a gaur can have a cow as a surrogate mother, defin itely not a monkey. But what about an extinct animals as unique as the panda? What species could possibly serve as a surrogate mother? Cloning presents many exciting possibilities. However, even if extinct animals are brought back, they could not survive in today’s world. Not only do most extinct animals have no habitat to love in, but the other plants and animals they depended on for food may also be gone as well. 1. It can be learned from the text that ________. A. scientists have cloned the African bongo antelope B. both the cheetah and the giant panda live in Asia C. the gaur lives in Asia and is enered D. the gaur is an extinct species 2. The underlined words “a surrogate mother” probably refer to a female who ----- A. contributes its eggs to another female  B. gives birth to a baby for another female C. gives birth to a baby of its own        D. cannot give birth to a baby 3. The difficulty in cloning an extinct species is the lack of ______. A. both the well-preserved DNA and plants to live on B. both the habitat to live in and the well-preserved DNA C. both habitat to live in and plants to live on D. both the well-preserved DNA and a surrogate mother 4. In the author’s opinion, it is possible that ______. A. some extinct species may be cloned, but not survive B. extinct species may be cloned and easily survive C. a gaur can hav e a monkey as a surrogate mother D. all the extinct species may be cloned 5.Today , have scientists  cloned  dinosaus? A .Yes    B .No    C .A lot  D.Only one.

题目标签:羚羊
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【单选题】Large animals that inhabit the desert have evolved a number of adaptations for reducing the effects of extreme heat. (31) adaptation is to be light in color, and to (32) rather than absorb the sun...

A.
Another strategy (37) large desert animals is to tolerate the loss of body water to a point (38) would be fatal for non-adapted animals. The camel can lose up to 30 percent of its body weight (39) water without harm to itself, (40) human beings die after losing only 12 to 13 percent of their body weight. An equally important adaptation is the ability to (41) this water loss (42) one drink. Desert animals can drink prodigious’ volumes in a short time, and camels have been known to (43) over 100 liters in a few minutes. A very dehydrated person, (44) , cannot drink enough water to rehydrate at one (45) , because the human stomach is not sufficiently big and because a too rapid (46) of the body fluids causes death from water intoxication. The (47) of water loss is of obvious advantage in the desert, as animals do not have to remain (48) a water hole but can obtain food from grazing sparse and far-flung pastures. Desert-adapted mammals have the (49) ability to feed normally when extremely dehydrated; it is a common experience in people that appetite is lost even (50) conditions of moderate thirst.

【单选题】Large animals that inhabit the desert have evolved a number of adaptations for reducing the effects of extreme heat. (31) adaptation is to be light in color, and to (32) rather than absorb the sun...

A.
Another strategy (37) large desert animals is to tolerate the loss of body water to a point (38) would be fatal for non-adapted animals. The camel can lose up to 30 percent of its body weight (39) water without harm to itself, (40) human beings die after losing only 12 to 13 percent of their body weight. An equally important adaptation is the ability to (41) this water loss (42) one drink. Desert animals can drink prodigious’ volumes in a short time, and camels have been known to (43) over 100 liters in a few minutes. A very dehydrated person, (44) , cannot drink enough water to rehydrate at one (45) , because the human stomach is not sufficiently big and because a too rapid (46) of the body fluids causes death from water intoxication. The (47) of water loss is of obvious advantage in the desert, as animals do not have to remain (48) a water hole but can obtain food from grazing sparse and far-flung pastures. Desert-adapted mammals have the (49) ability to feed normally when extremely dehydrated; it is a common experience in people that appetite is lost even (50) conditions of moderate thirst.

【单选题】Large animals that inhabit the desert have evolved a number of adaptations for reducing the effects of extreme heat. (31) adaptation is to be light in color, and to (32) rather than absorb the sun...

A.
Another strategy (37) large desert animals is to tolerate the loss of body water to a point (38) would be fatal for non-adapted animals. The camel can lose up to 30 percent of its body weight (39) water without harm to itself, (40) human beings die after losing only 12 to 13 percent of their body weight. An equally important adaptation is the ability to (41) this water loss (42) one drink. Desert animals can drink prodigious’ volumes in a short time, and camels have been known to (43) over 100 liters in a few minutes. A very dehydrated person, (44) , cannot drink enough water to rehydrate at one (45) , because the human stomach is not sufficiently big and because a too rapid (46) of the body fluids causes death from water intoxication. The (47) of water loss is of obvious advantage in the desert, as animals do not have to remain (48) a water hole but can obtain food from grazing sparse and far-flung pastures. Desert-adapted mammals have the (49) ability to feed normally when extremely dehydrated; it is a common experience in people that appetite is lost even (50) conditions of moderate thirst.

【单选题】Large animals that inhabit the desert have evolved a number of adaptations for reducing the effects of extreme heat. (31) adaptation is to be light in color, and to (32) rather than absorb the sun...

A.
Another strategy (37) large desert animals is to tolerate the loss of body water to a point (38) would be fatal for non-adapted animals. The camel can lose up to 30 percent of its body weight (39) water without harm to itself, (40) human beings die after losing only 12 to 13 percent of their body weight. An equally important adaptation is the ability to (41) this water loss (42) one drink. Desert animals can drink prodigious’ volumes in a short time, and camels have been known to (43) over 100 liters in a few minutes. A very dehydrated person, (44) , cannot drink enough water to rehydrate at one (45) , because the human stomach is not sufficiently big and because a too rapid (46) of the body fluids causes death from water intoxication. The (47) of water loss is of obvious advantage in the desert, as animals do not have to remain (48) a water hole but can obtain food from grazing sparse and far-flung pastures. Desert-adapted mammals have the (49) ability to feed normally when extremely dehydrated; it is a common experience in people that appetite is lost even (50) conditions of moderate thirst.

【单选题】As we all know, the number of Tibetan antelopes(藏羚羊) ________ becoming ___________.

A.
is; less and less
B.
are; less and less
C.
is; smaller and smaller
D.
are; smaller and smaller