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  3. Running a lever was once thought to be the prerogative of warm-blooded creat

Running a lever was once thought to be the prerogative of warm-blooded creat

游客2024-06-11  51
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. [br] Scorpions injected with prostaglandins move to hot areas to ______.
选项 A、engage in greater activity
B、seek out a more-iron environment
C、demonstrate that they are ill
D、develop a fever and flight bacterial infections
答案 D
解析 文章第三段开头就说明了：…moderate fevers have their benefits, which might explain why the fever process is xo widespread.(适度的升温有利，这也许解释了为什么升温过程应用如此广泛。)这解释了为什么被子注入前列腺素的蝎子向炎热地区运动。A、C两项在文章中无法找到依据，百B项与文章内容相抵触，因此D项为正确答案。
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