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

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.
Fevers cause ______.
选项 A、prostaglandins to be formed
B、iron to be made available to bacteria
C、leukocytes to be more mobile
D、lizards to be cold-blooded animals
答案C
解析 本题答案选择C项是根据文章最后一段中Leukocytes，white blood cells that are active in fighting bacterial infectious，are more mobile at febrile temperature．(积极参与抵抗细菌人侵的白血球在高温下更加活跃。)而作出的，A项和B项的叙述与文章不相符，而D项虽是正确的表述，但与本题毫不相关，因此要舍弃。
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