問題詳情

55至58題Most of the so-called experts may tell people that exercise does good to them at any age and aids in making them healthier and even fight depression. However, according to a new study conducted by David Gershon, a biologist, exercise could be unhealthy, especially for people past middle age. The study was done with mice. It showed that although mild exercise had a positive effect on the muscles of young mice, it damaged the muscles of mice past middle age.In the experiment, the three groups of mice corresponded in age to young, middle-aged, and elderly humans. The mice were placed on a treadmill 30 minutes a day for a five-week period. At the end of that time, the young mice's hind-leg muscles had increased almost 30 percent in weight, but those of elderly mice were reduced by 25 percent. No clear pattern showed for the middle-aged mice.David explained that the older mice's muscles were probably already breaking down and that exercise worsened the condition. An earlier study by David showed that middle-aged mice benefited from exercise if they started exercising young and continued it. It's clear that because the tests were done on mice, drawing conclusions about humans can be risky. But the studies do challenge the theory that exercise is good under any conditions. Let's use the tests on mice as a springboard for other studies.
55.According to the passage, the purpose of David's experiment was to_.
(A) train biologists
(B) encourage people to exercise
(C)maintain the health of mice
(D) apply the findings to humans

參考答案

答案：D[無官方正解]
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)

內容推薦

內容推薦