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9. I __________ the Christmas gift by mail because he came home during the Christmas holidays. A. ought to have sent       B. couldn't have sent C. must have sent         D. needn't have sent

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8. It is predicated that existing reserves of fossil fuel ______ by 2045. A. have been run out      B. are going to be run out C. will have run out       D. have run out

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7. As the train will not leave until one hour later, we __________have a drink at the cafe.

A. may well     B. just as well    C. might as well    D. as well

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6. Scientists think ______ helps some trees to conserve water in the winter. A. when losing leaves  B. leaves are lost  C. that losing leaves  D. the leaves lost

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5. __________in the past, at the moment it is a favorite choice for wedding gown. A. Unpopular has as white been    B. White has been as unpopular C. Unpopular has been as white    D. Unpopular as white has been

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4. He never hesitates to make _____ criticisms ______ are considered helpful to others. A. so, that      B. so, as      C. such, that     D. such, as

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3. The sale usually takes place outside the house, with the audience __________ on benches, chairs or boxes.   A. having seated    B. seating      C. seated     D. having been seated

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2. ______there is little we can do to modify the weather, we can at least know what kind of weather to expect.   A. Since      B. When       C. While     D. Unless

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第一节  语法和词汇知识: ( 共20小题; 每题0.5分, 满分10分 )

Ⅰ. 从A、B、C、D四个选项中, 选出可以填入空白处的最佳选项, 并在答题卷上将该项涂黑。

1. Many people have come to realize that they should go on   _ balanced diet and make  ____ room in their day for exercise.

  A. a;/        B. the; a       C. the; the     D./;a

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54.(12分)我国科研人员发现,弯曲的蚕丝由于弯折处易断裂,其强度低于由蜘蛛纺绩器拖牵出的直丝,并首次在世界上通过了转基因方法将“绿色荧光蛋白基因”与“蜘蛛拖牵丝基因”拼接后成功插入蚕丝基因组中,并在受体细胞中成功表达。 

(1)在这项“基因工程”的操作中,目的基因是   ,采用绿色荧光蛋白基因的主要目的是     

(2)两基因组合在导入受体细胞前必须进行的步骤是:将其与由细菌体内取得的    进行切割处理,以保证有相同的        ,并拼接成        。完成这一步骤常规的处理方法是:①             ②           。如果引入的受体细胞是细菌,还要对细菌作         处理。

(3)在基因工程中受体常用微生物,为什么? 

                                   

(4)“蜘蛛拖牵丝基因”成功表达的标志是              

(5) 通过上述转基因方法获得的转基因蚕,将来产生的配子中是否一定含有“蜘蛛拖牵丝基因”?        

(6)带有“绿色荧光蛋白基因”的转基因蚕,是否能引起生态安全性问题?请分析原因。                                       

杭十四中二〇〇九学年第一学期9月月考

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