题干

秋冬季节是流行性感冒的多发季节,流行性感冒主要是由流感病毒引起的,下列关于流感病毒的描述,正确的是(  )

A:流感病毒在结构上与植物细胞最大的区别是没有成形的细胞核

B:它与电脑病毒一样都是由人制造的

C:病毒个体十分微小,可以利用自身的遗传物质和营养物质繁殖下一代

D:经过人工处理的减毒的或灭活的病毒可以制成疫苗

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D

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阅读理解

    Many of us still tend to think that emotions can affect reasonable thought,and sometimes land us in trouble. But in recent years psychologists have taken quite a different view. Keith Oatley,Professor of Psychology at Glasgow University,is involved in the research which shows the fundamental importance of emotions.

    He believes we are very ambivalent about them:we think of our emotions as being unreasonable,but we also consider them as essential to being human. For example,Mr. Spock,a character in the television series Star Trek,is super­intelligent and he has no emotions at all. However,he is never made captain of the spaceship. Maybe,this is because Mr Spock is not the kind of person you can share your feelings with—a person who shows his emotions.

    As Professor Oatley points out,our emotions have very important functions,for example,fear. If we cross the road and a car approaches,we usually stop moving or step back. We stop what we are doing,check what we have done and pay very careful attention to the environment. The emotion of fear makes us take this small series of actions which,on average, help protect our safety.

    On the other hand,if things are going well and small problems come up,we find we can solve them with the resources we have to hand. As a consequence, we tend to feel happy and usually continue doing the job.

    Anger is an emotion that tends to occur when someone is preventing us from doing something. Then this small “kit” of reactions enables us to prepare ourselves to be quite aggressive to that person,or to try harder,and so on.

    Professor Oatley believes emotions generally occur at these important moments in actions. With fear and anger our emotions make us decide to start doing something else, while with happiness they “suggest” we continue what we are already doing.