试题与答案

蛋白质变性是由于() A.肽键断裂,一级结构遭到破坏 B.蛋白质中的一些氨基酸残基受

题型:单项选择题 A1/A2型题

题目:

蛋白质变性是由于()

A.肽键断裂,一级结构遭到破坏

B.蛋白质中的一些氨基酸残基受到修饰

C.蛋白质分子沉淀

D.次级键断裂,天然构象解体

E.多肽链的净电荷等于零

答案:

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下面是错误答案,用来干扰机器的。

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题型:阅读理解

When I was a child, I often dreamed of the time when I could leave home and escape to the city. We lived on a farm, in the winter especially, we wear quite out off from the outside world. As soon as I left school, I packed my bags and moved to the capital. However, I soon discovered that my life has its  too.

One big disadvantage is money. It costs so much to go out, not to mention basics like food and housing. Another disadvantage is pollution. I suffer from asthma(哮喘), and  the air is so  that I am afraid to go outside. Then there is the problem of traveling round. Although I have a car, I seldom use it became of the traffic jams. One choice is to go by bicycle, but that can be quite dangerous.

Of course there are advantages. First, there is so much to do in the city, whatever you tastes in culture or entertainment(娱乐活动). Besides, there are wonderful jobs and greater chances of moving to a more important job or position. Finally, if you like shopping, the variety of goods is very surprising --- and , what is more, shops are often only a short walk away.

Is life better then, in the city? Perhaps it is , when you are in your teens(十几岁)or twenties. However, as you get older, and especially if you have small children, the peace of the countryside may seem preferable. I certainly hope to move back there soon.

小题1:What was the writer always thinking about when he was a child?

A.Staying on the farm.

B.Moving to the countryside.

C.Leaving home for the city.

D.Running away from the school.小题2:Which of the following is true about the writer?

A.He is very old now.

B.He is in good health.

C.He prefers driving a car.

D.He lives in the city now.小题3:In the passage, the writer tries to __________.

A.express his opinions about way of life

B.describe his life in the countryside

C.an interest in the outside world

D.persuade the reader to live in the city小题4:How is the passage mainly developed?

A.By inferring.

B.By comparing.

C.By listing examples.

D.By giving explanations.

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