试题与答案

关于LD50,下列叙述正确的是() A.LD50是绝对致死剂量,是指化学物引起全部受

题型:单项选择题

题目:

关于LD50,下列叙述正确的是()

A.LD50是绝对致死剂量,是指化学物引起全部受试对象死亡的剂量

B.化学物质的急性毒性越大,其LD50值越小

C.LD50是一个生物学参数,因而不受实验动物种属和接触途径的影响

D.LD50是通过一次实验观察所得到的参数

E.化学毒物不引起受试对象出现死亡的剂量是LD50

答案:

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题型:阅读理解

Many of us feel uneasy when someone stands too close to us, talks to us too loudly or makes eye contact(接触) with us for too long. But have you ever wondered why those things make you uncomfortable?

It’s all about personal peace, which means not only an imaginary space around the body, but also the space around all the senses. People feel that their space is being violated(侵犯) when they meet with an unwelcome sound, smell or look. This is probably why a man on a crowded bus shouting into his mobile phone or a woman next to you putting on strong perfume(香水) makes you feel angry.

Whether people have had a stronger wish to protect their personal space in recent times is hard to say. Yet studies of airlines show that people have a strong desire(渴望) to have space to themselves. In a survey by TripAdvisor, a travel website, people said that if they had to pay more for some extra service, they would rather have larger seats than extra food.

Although people may need their personal space, some hardly realize it. For example, people on a bus who hold newspapers in front of their faces to read in fact keep a distance from strangers.

Go and watch a library table. You will notice that one of the corner seats will usually be taken first, because they are the farthest way. What if someone sits opposite to you? Maybe you will pile up books as if to make a wall.

Preference(偏好) for personal space are different from culture to culture. Scientists have found that Americans generally prefer more personal space than people from other cultures. In Latin(拉丁人的) cultures, however, people are more comfortable standing close to each other.

小题1:The writer mainly _________ in this article.

A.tells us how to achieve personal space

B.explains why people need personal space

C.introduces some knowledge about personal space

D.argues for the importance of keeping personal space小题2:Who might feel his personal space is safe according to the passage?

A.A person who has to sit next to a lady putting on strong perfume.

B.A person who has been watched by a stranger for a long time.

C.A person who hears strange noises when reading at home.

D.A Latin boy who is chatting with a friend sitting close to him.小题3:What can we know from the survey by TripAdvisor?

A.People need a smaller personal space in recent times than before.

B.People have a strong desire for personal space in recent times.

C.There are not enough seats on the plane to meet people’s needs.

D.Food service is better provided than seats on the plane.小题4:Which of the following is TRUE according to the passage?

A.The space around the body is more needed than that around all the senses.

B.If you hold newspapers on the bus, your personal space won’t be violated.

C.People usually choose the corner seats first in a library for personal space.

D.Different cultures share the same preferences for personal space.

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