Running a lever was once thought to be the prerogative of warm-blooded creatures, whose internal temperatures are independent of

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问题     Running a lever was once thought to be the prerogative of warm-blooded creatures, whose internal temperatures are independent of the weather. But, as Matthew Kluger reported in "The Importance of Being Feverish" (January 1976), lizards can also develop fevers, even though there is no question that they are cold-blooded. They raise their temperatures by moving into the sun or, in the case of Kluger’s experiments, under a sun lamp. And it seems to do them some good. Sick lizards kept in cages at feverish temperatures fare much better than their counterparts in normal mid cool environments.
    Now, fever has spread to invertebrates(无脊椎动物). Recent studies have shown that crayfish and scorpions can develop fevers. Crayfish injected with bacteria and scorpions injected with prostaglandins(前列腺素) swam and scuttled to hot areas. (Prostaglandins are hormones thought to be instrumental in the development of a fever. )
    Evidence is also mounting that moderate fevers have their benefits, which might explain why the fever process is so widespread. Leukocytes, white blood cells that are active in fighting bacterial infections, are more mobile at febrile temperatures. And fevers reduce the amount of iron available to bacteria. That reduction, combined with high temperatures, has been shown to inhibit bacterial growth.
Which of the following statements is true?

选项 A、Developing fever is the privilege of warm-blooded animals, so sick lizards can not run a fever.
B、Invertebrates also have the ability to raise their temperature,
C、The internal temperatures of warm-blooded creatures are independent of the weather, so are the cold-blooded animal.
D、Sick lizards move into the sun to develop lever.

答案B

解析 文章第一段开始两句话告诉我们升高体温曾被认为是热血动物的特权,但是冷血动物也同样具有这种能力,蜥蜴就是一个例子,因此A项不正确。文章第二段Now,fever has spread to invertebrates.(现在,升高体温的能力扩展到了无脊椎动物。)由此可见B项“无脊椎动物也具有升高体温的能力”是正确答案,C项中所说热血动物的体内温度是独立于天气之外的,这是正确的说法,但冷血动物是否也如此,文章并未提及,故放弃。生病的蜥蜗是呆在笼子里以求体温升高,所以D项也不正确。
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