共用题干 A Biological ClockEvery living thing has what scientists call a biological clock that controls behavior. The bio- logical clock tells______(51)when to form flowers and when the flowers should open. It tells ______(52)when to leave the protective coco

题目

共用题干
A Biological Clock
Every living thing has what scientists call a biological clock that controls behavior. The bio- logical clock tells______(51)when to form flowers and when the flowers should open. It tells ______(52)when to leave the protective cocoons and fly away,and it tells animals and human beings when to eat,sleep and wake.
Events outside the plant and anima______(53)the actions of some biological clocks.Sci- entists recently found,for example,that a tiny animal changes the color of its fur______(54) the number of hours of daylight.In the short______(55)of winter,its fur becomes white.The fur becomes gray brown in color in the longer hours of daylight in summer.
Inner signals control other biological clocks.German scientists found that some kind of internal clock seems to order birds to begin their long migration______(56)twice each year. Birds ______(57)flying become restless when it is time for the trip,______(58)they become calm again when the time of the flight has ended.
Scientists say they are beginning to learn which______(59)of the brain contain biologica] clocks.An American researcher,Martin Moorhead,said a small group of cells near the front of the brain______（60)to control the timing of some of our actions.These______(61)tell a person when to______(62),when to sleep and when to seek food.Scientists say there proba- bly are other biological clock cells that control other body activities.
Dr Moorhead is studying______(63)our biological clocks affect the way we do our work .For example,most of us have great difficulty if we must often change to different work hours.
______(64)can take many days for a human body to accept the major change in work hours .Dr. Moorhead said industrial officials should have a better understanding of biological clocks and how they affect workers.He said______(65)understanding could cut sickness and accidents at work and would help increase a factory's production.

65._________
A: if
B:such
C: with
D: so

参考答案和解析

答案：B

解析：

从后半句when to form flowers and when flowers should open知道，只有plants才有花。前面没有定冠词修饰的plants是泛指植物这一大类，与动物类相对应。

后面出现的when to leave the protective cocoons and fly away提示我们，唯有选in-sects才是正确的，因为只有insects才有protective cocoons，而birds、 fish和snakes都没有。

affect作为动词是“影响”的意思，而effect作为动词则是“使发生，使生效”的意思。这里谈论的是动植物生物钟的一般情况，所以使用动词的一般现在时。

这里应使用介词短语，因为其后是名词。because和since都有“因为”的意思，但它们都是连词，用来引导原因状语从句，for the reason that后接句子，所以也不是答案。

根据下句中的in the longer hours of daylight in summer和上句中的the number of hours of daylight，以及该段的中心思想，可以判断，应选择B，因为冬天日短夜长，夏天则反之。

本句中有birds , migration这些词，下一句又谈及迁徒飞行前的躁动不安，就知道应该填词义为“飞行”的名词。fly是动词，不能选择；其他两个选项也都不合适。flight是 fly的名词形式，所以是合适的选择。

该句句子的主干是：主语birds，谓语become restless。所以，所填的词是过去分词，修饰birds。从上下文表达的意思判断，ordered by（被命令）、he1ped by（被帮助）和in- truded on（被强加）都不匹配，只有prevented from是合适的选择。

很明显，这里需使用连词，连接该句中平行的两个分句。而根据整个句子的句意，上半句和下半句形成反差对比：become restless when the time of the flight has ended，所以应选择 but，表示相反的两层意思。

portion是“一定数量，一份”, section是“切下的部分”, kind是“种类”，都不符合上下文意思连贯的要求。唯有B是正确的选项。

不能选择C，因为主语是group，而不是cells，所以要采用动词的第三人称单数形式 seems 。 A和B不符合常识。

These一词说明，其后名词是上文已经提到的某些事物，即cells。从下文中可以看出，尽管actions一词也在上文中出现，但该词不符合句意。选项A和B意思不准确。

该句中的三个宾语都是带疑问副词的动词不定式，所以都要用动词原形。awaken 是唯一合适的选择，woke是wake的一般过去形式，awakening是形容词，wake-up是名词。

studying后面是一个从句作它的宾语，而从句起首处应有个连词。把C或D填入空格，上下文意思不连贯。根据下文的例子，作者讨论的不是生物钟为什么会影响我们的工作，而是生物钟如何影响我们的工作。所以，how是正确的选择。

从句子结构中不难看出，to accept the major change in work hours是实际上的主语，而此处需要一个形式主语，所以只能选择It。

该句中的understanding既然是上句中提到的better understanding , C便是最佳的选项。其他三个选项均不符合语法。

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