The term biological clock is applied to the means, which living things 【M1】______ adjust their activity patterns, withou

admin2009-10-19  41

问题 The term biological clock is applied to the means, which living things         【M1】______
adjust their activity patterns, without any obvious cue, the time of day, or   【M2】______
the month, or the year. They are affected but little, if at all, by drugs,
chemical, or wide temperature differences—factors may alter substantially     【M3】______
the rates of all ordinary processes of the body.
    The nature of the biological clocks mechanism is still a mystery. Two      【M4】______
quite different theories have been advanced to account to them. According      【M5】______
to the first of these theories, each individual have evolved, aided by natural
selection, an adaptation to the rhythmic environment. It has now               【M6】______
become independence on the environment. According to this view, the clocks     【M7】______
are not perfect timers. They require regular corrections by the natural light
and tide cycles and the changed lengths of the day throughout the year.        【M8】______
The other theory holds up living things react continuously to their            【M9】______
rhythmic physical environment. The setting of their biological clocks,
therefore, involves a constant adjustment to subtle clocks are potential       【M10】______
perfect timers.
【M3】

选项

答案factors ∧→which/that

解析 定语从句中which/that做主语,故不可省略
转载请注明原文地址:https://kaotiyun.com/show/Bnt7777K
0

随机试题
最新回复(0)