题干

下列与遗传有关的几种酶的说法不正确的是

A:限制性核酸内切酶识别特定的脱氧核苷酸序列,体现了酶具有专一性

B:DNA连接酶连接的是两个DNA片段,DNA聚合酶连接DNA片段与单个脱氧核苷酸

C:解旋酶能够打开氢键,在细胞分裂期数量多并且有较高活性

D:RNA聚合酶在RNA复制和转录中起作用,其催化活性受温度影响

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C

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    In the clinic, I asked if Michael could be retested, so the doctor tested him again. To my   1,   it was the same score. Later that evening, I   2  told my husband, Frank what I had   3  that day. After talking it over, we agreed that we knew our4much better than an IQ test. We5 that Michael's score must have been a 6and we should treat him naturally as usual.
    We moved to Indiana in 1962, and Michael studied at Concordia High School in the same year. He got 7 grades in the school,   8   in biology and chemistry, which was a great comfort.
    Michael 9 Indiana University in 1965 as a medical student, after that, his teachers asked him to take more courses than required. In 1968, he was accepted by the School of Medicine, Yale University.
    On graduation day in 1972, Frank and I  10 the ceremony at Yale11the ceremony, we told Michael about the low IQ score he got when he was six. Since that day, Michael sometimes would look at us and say jokingly,   “My dear mom and dad never told me that I couldn't be a doctor, not until after I graduated from medical school!” It is his special way of thanking us for the 12we had in him.
    Interestingly, Michael then asked for   13 IQ test. We went to the same clinic where he had received the test eighteen years before. This time Michael scored 126, an increase of 36 points. A result like that was supposed to be   14  .
    Children often do as well as what adults, particularly parents and teachers, expect of them. That is, tell a child he is “ 15 ”, and he may play the role of a foolish child.