下图是蚕豆叶不同切面结构示意图。在“制作与观察蚕豆叶下表皮的临时装片”实验中,低

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问题:

下图是蚕豆叶不同切面结构示意图。在“制作与观察蚕豆叶下表皮的临时装片”实验中,低倍镜视野下观察到数目最多的细胞是

[ ]

A.②                

B.③                

C.④              

D.⑤

考点:叶片的结构
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工艺气温度高则其()上升。

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根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

I had an experience once which taught me something about the ways people made a bad situation worse by blaming themselves. One January, I officiated(主持) at two funerals for two elderly women. 小题1:. At the first home, the son of the deceased(已故) woman said, “If only I had sent my mother to Florida and gotten her out of this cold and snow, she would be alive today. It’s my fault that she died.” At the second home, the son said, “If only I had not insisted her going to Florida, she would be alive today.  小题2: . It is my fault.”

When things don’t turn out as we would like them to, we tend to assume that had we done things differently, the story would have had a happier ending. Any time there is a death, the survivors will feel guilty. Because the course of action they took turned out bad, they believe that the opposite course, for example, keeping mother at home, would have turned out better.     小题3: 

There seem to be elements involved in our readiness to feel guilty. The first lies in our belief that the world makes sense---there is a reason for everything that happens. 

The second is the thought that we are the cause of what happens, especially the bad things that happen.小题4:. A baby comes to think that the world exists to meet his needs, and that he makes everything happen in it. He wakes up in the morning and calls the rest of the world to its tasks.小题5: . When he is hungry, people feed him, and when he is wet, people change him. Very often, we do not completely abandon that childish thought that our wishes cause things to happen.

A.That long airplane ride was more than she could take

B.After all, how could it have turned out any worse?

C.Life and dead is an unsolved mystery.

D.The roots of this feeling may lie in our childhoodE.He cries, and someone comes to attend to him

F.Both died a natural death

G. They believe that they are responsible for what has happened.

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下列属于致死剂量的是()。

A.NOAEL

B.Zac

C.LOEL

D.ADI

E.LD50

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尿干化学试带的碘酸盐层的作用是 ()

A.破坏维生素C的干扰

B.防止大分子物质干扰

C.检测维生素C

D.使尿液快速、均匀吸入

E.保护试带模块

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比较供应商调查各方法的优缺点。

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