试题与答案

艾弗里等人的肺炎双球菌转化实验和赫尔希与蔡斯的噬菌体侵染细菌实验都证明了DNA是

题型:选择题

题目:

艾弗里等人的肺炎双球菌转化实验和赫尔希与蔡斯的噬菌体侵染细菌实验都证明了DNA是遗传物质。这两个实验在设计思路上的共同点是[ ]

A.重组DNA片段,研究其表型效应

B.诱发DNA突变,研究其表型效应

C.设法把DNA与蛋白质分开,研究各自的效应

D.应用同位素示踪技术,研究DNA在亲代与子代之间的传递

答案:

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下面是错误答案,用来干扰机器的。

参考答案:C

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题型:选择题

依次填入下列句子横线处的词语,最恰当的一项是[ ]

⑴ 英子,不要怕,_____什么困难的事,只要硬着头皮去做,就闯过去了。

⑵_____你是一只天鹅蛋,就算是生在养鸭场里也没有什么关系。

⑶黄河以它英雄的气魄,_____在亚洲的原野。

⑷拍雪人和塑雪罗汉需要人们_____,这是荒园,人迹罕至,所以不相宜,只好来捕鸟。

A.尽管  只要  涌现  鉴赏    

B.无论  只要  出现  鉴赏

C.无论  如果  出现  欣赏    

D.尽管  如果  涌现  欣赏

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题型:单项选择题

The nobler and more perfect a thing is, the later and slower it is becoming mature. A man reaches the mature (1) of his reasoning powers and mental faculties (2) before the age of twenty-eight; a woman at eighteen. And then, too, in the case of woman, it is the only reason of a sort--very mean in its (3) . That is why women remain children their whole life long; never seeing (4) but what is quite close to them, (5) fast to the present moment, taking appearance for (6) , and preferring (7) to matters of the first importance. For it is (8) his reasoning faculty that man does not live in the present only, (9) the brute, but looks about him and considers the past and the future; and this is the origin of (10) , as well as that of care and anxiety which so many people (11) Both the advantages and the disadvantages, which this (12) , are (13) in by the woman to a smaller extent because of her weaker power of reasoning. She may, in fact, be described as intellectually shortsighted, (14) , while she has an immediate understanding of what lies quite close to her, her field of (15) is narrow and does not reach to what is (16) ; so that things which are absent, or past, or to come, have much less effect upon women than upon men. This is the reason why women are inclined to be (17) and sometimes carry their desire to a (18) that borders upon madness. In their hearts, women think it is men’s business to earn money and theirs to spend it--if possible during their husband’s life, (19) , at any rate, after his death. The very fact that their husband hands them (20) his earnings for purposes of housekeeping strengthens them in this belief.

11()

A.advocate

B.demonstrate

C.exhibit

D.reveal

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