问题 选择题

在“观察人口腔上皮细胞”的实验中,下列关于显微镜的操作方法正确的是(  )

A.观察时用右眼观察

B.转动粗准焦螺旋使镜筒下降时,眼睛要看着目镜

C.对光时,转动反光镜,通过目镜看到白亮的圆形视野即可

D.视野中要观察的物像偏左下方,要移到视野中央,应向右上方移动玻片标本

答案

A、观察时用左眼观察,右眼记录,故错误;

B、转动粗准焦螺旋使镜筒下降时,为避免压破标本,眼睛要看着物镜,故错误;

C、在对光这时,应左眼注视目镜(右眼睁开),转动反光镜,直到看到一个白亮的视野,说明光线能够通过,对光成功,故正确;

D、我们在显微镜下看到的物像是上下左右均颠倒的物像,所以我们移动玻片标本时,标本移动的方向正好与物像移动的方向相反.如我们向右移动玻片标本,而在显微镜内看到的物像则是向左移动的.所以如果要观察的细胞位于视野的左下方,可将玻片向左下方移动,故错误.

故选:C.

完形填空

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第二节:完形填空(共20小题;每小题1.5分,满分30分)

阅读下面短文,掌握其大意,然后从36-55各题所给的四个选项(A、B、C和D)中,选出最佳选项。

I was working in a store three years ago. I remember one girl who started   36   there a few months after me. I remember always meeting her. I don’t know   37   but for a strange reason we would never talk. We would just see each other and smile.

She would    38   smile in a really happy way until one day when we got to work in the    39   department again. She    40   as if she was the happiest girl in the world. But I had a strange feeling. So I went up to her and asked,“What’s wrong with you?”She answered, “Why?”I said,“I could feel you’re very   41   today and you’re trying to hide it.”

She was shocked(震惊的) as if I had    42   her deepest secret, so we started    43 .

She told me why she was feeling like that and why she was    44   to hide it and we had a good time together. Time    45   and we became good friends. She’d always tell me I had changed her    46   in so many ways, but I could not    47   how it had happened. I would just smile, not understanding what she    48   by that.

Today this girl is one of my best    49  . I really don’t know what I would do    50  

her. She has been there for me in every possible way a friend could be.

I guess what I’m trying to say is you     51    know when you’re helping yourself. I

52   this girl never knowing that at the same time I was helping myself by finding a(n)

53    friend.

So the next time you see a    54   and he looks as if he needs    55   who will listen to him, listen to what he has to say. You never know, you might just end up helping yourself.

36.A.playing                   B.learning                  C.working                  D.living

37.A.why                       B.when                      C.where                     D.how

38.A.secretly                  B.hardly                    C.perhaps                   D.always

39.A.great                      B.same                      C.modern                   D.small

40.A.shouted                  B.cried                      C.spoke                     D.smiled

41.A.happy                     B.angry                            C.proud                     D.sad

42.A.kept                       B.told                        C.discovered                     D.watched

43.A.talking                   B.quarrelling              C.discussing               D.arguing

44.A.planning                 B.trying                     C.refusing                  D.failing

45.A.went off                 B.went by                  C.went up                  D.went down

46.A.life                        B.hobby                     C.habit                      D.manner

47.A.introduce                B.promise                  C.suggest                   D.imagine

48.A.meant                     B.wanted                   C.offered                   D.received

49.A.classmates               B.sisters                     C.friends                    D.workers

50.A.with                       B.without                   C.through                  D.besides

51.A.often                      B.sometimes               C.forever                   D.never

52.A.helped                    B.accepted                 C.recognized              D.praised

53.A.kind                       B.rich                        C.true                        D.honest

54.A.student                   B.stranger                  C.manager                 D.listener

55.A.someone                 B.anyone                   C.none                       D.everyone

单项选择题