Modern scientists divide the process of dying into two phases—clinical or temporary death and biological death. Clinical death o

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问题     Modern scientists divide the process of dying into two phases—clinical or temporary death and biological death. Clinical death occurs when the vital organs, such as the heart or lungs, have ceased to function, but have not suffered permanent damage. The organism can still be revived. Biological death occurs when changes in the organism lead to the disintegration of vital cells and tissues. Death is then irreversible and final.
    Scientists have been seeking a way to prolong the period of clinical death so that the organism can be reanimated before biological death occurs. The best method developed so far involves cooling of the organism, combined with narcotic (麻醉的,催眠的) sleep. By slowing down the body’s metabolism, cooling delays the processes leading to biological death.
    To illustrate how this works, scientists performed and experimented on a six-year-old female baboon (狒狒) called Keta. The scientists put Keta to sleep with a narcotic. Then they surrounded her body with ice bags and began checking her body temperature. When it had dropped to 28 degrees the scientists began draining blood from an artery. The monkey’s blood pressure decreased and an hour later both the heart and respiration stopped; clinical death set in. For twenty minutes Keta remained in this state. Her temperature dropped to 22 degrees. At this point the scientists pumped blood into an artery in the direction of the heart and started artificial respiration. After two minutes the baboon’s heart became active once more. After fifteen minutes, spontaneous respiration began, and after four hours Keta opened her eyes and lifted her head.After six hours, when the scientists tried to give her a penicillin injection, Keta seized the syringe (注射器) and ran with it around the room. Her behavior differed little from that of a healthy animal.
According to the passage, the function of cooling an organism is to______.

选项 A、speed up the body’s metabolism
B、slow down disintegration of body tissues
C、prevent damage to organs
D、revive damaged organs

答案B

解析 这是一道细节题。文中第二段最后一句说:“通过减缓机体的新陈代谢,冷冻使导致生物死亡的过程延缓了下来。”B符合文中内容。本题通过排除法亦可找到答案。A与文中第二段最后一句内容相矛盾,可排除;C“阻止对器官的破坏”和D“可以恢复已经受损的器官的功能”,文中均未涉及,可排除。
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