0  287039  287047  287053  287057  287063  287065  287069  287075  287077  287083  287089  287093  287095  287099  287105  287107  287113  287117  287119  287123  287125  287129  287131  287133  287134  287135  287137  287138  287139  287141  287143  287147  287149  287153  287155  287159  287165  287167  287173  287177  287179  287183  287189  287195  287197  287203  287207  287209  287215  287219  287225  287233  447090 

9. As long as you keep on working hard like this, you’ll be _______ into a university you’d like sooner or later.

     A. given           B. permitted           C. admitted           D. taken

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8. You ________ step into the same river twice. Everything is changing.

     A. can’t           B. shouldn’t        C. mustn’t          D. daren’t

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7. If the weather had been better yesterday, we could have had a picnic. But it ______ all day.

     A. has rained       B. rains            C. rained              D. had rained

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6. Jack and Peter would like to go to the concert, but _______ has got a ticket.

     A. both of whom     B. both of them  C. neither of them      D. neither of whom

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5. She remained _______ there for a good hour, which surprised all the other students.

     A. to stand         B. stand               C. stood               D. standing

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4. One thousand dollars a month is not a fortune but would help cover my living _______.

     A. bills             B. expenses        C. prices              D. charges

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3. We all know it will be next June _______we can really have a rest.

     A. when           B. before               C. since            D. until

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2. --How about _________ evening party this weekend?

  --That’s great. I’m sure it will be ________ success.

     A. an; a        B. the; a               C. an; 不填         D. the; 不填

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第一节:语法和词汇知识(共15小题;每小题1分,满分15分)

1. --My mum is ill in hospital. I’m so worried.

  --____________. I think she will be better soon.

     A. Take your time                         B. Take it easy  

C. Don’t mention it                    D. You must be joking

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34.(8分) 植物叶绿素的合成需多种条件,如光照、适宜的温度和必要的矿质元素等。为验证叶绿素合成需要的条件,有人设计了如下实验:

实验步骤:

①  配制含有蔗糖、水、琼脂及植物必需的所有矿质元素的1号培养基和不含Mg2+(其它成分与1号相同)的2号培养基,调至适宜pH备用。

②  取250mL锥形瓶四个,标号甲、乙、丙、丁,并分别装入等量的培养基。甲、丙、丁装入1号培养基, 乙装入2号培养基,并进行灭菌处理,然后冷却。

③  选取40粒小麦种子,用清水浸泡后,消毒,将种子的胚剥落下来,去掉胚乳,在无菌条件下,将胚等量接种在四个锥形瓶的培养基上。

④  将四个锥形瓶置于以下条件下培养:

甲和乙:充足光照,适宜温度30℃;丙:                ;丁:充足光照,温度10℃。

实验结果:

组别




幼苗颜色
绿色
黄色
黄色
黄绿色

请分析回答下列问题:

(1)请在上述实验步骤中补充丙组的实验条件。

(2)为什么每个锥形瓶中均接种10粒种子的胚,而不是只接种1粒种子的胚?

                                        

(3)实验中为何不采用完整的种子,而是去掉胚乳,将胚接种在培养基上萌发?

                                        

(4)甲组在此实验中的作用是             

2009~2010学年度第一学期 期中试卷

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