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问题 单项选择题

孕妇属于高危妊娠范围的是()。

A．孕妇年龄＞18岁

B．妊娠前体重＞40kg

C．妊娠前体重＜80kg

D．孕妇身高＜140cm

E．孕妇血压17.4/10.7kPa(130/80mmH

答案

参考答案：D

解析：[知识点] 高危妊娠

阅读理解

阅读理解,正确的写(T)，错误的写(F) (5分)

Mr. Smith is an English man. He teaches English well. His English classes are very interesting. He likes us and we like him, too.

Mr. Smith has two children—Tom and Mary. Tom is seven and his sister, Mary, is four. Tom goes to school but Mary doesn’t .Mr. Smith likes wearing(穿) a T-shirt and jeans (牛仔裤).Football is his favorite sport. After school we often have a baseball match. Sometimes Mr. Smith watches and joins us. He plays baseball just for fun.

根据短文内容判断正(T)误(F).

1. Mr. Smith is an English teacher.

2. Mr. Smith has one daughter.

3. Mary doesn’t go to school because she likes sports.

4. Mr. Smith likes to have sports.

5. We often play baseball with Mr. Smith.
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选择题

多聚酶链式反应（PCR）是一种体外迅速扩增DNA片段的技术。PCR过程一般经历下述三十多次循环：95℃下使模板DNA变性．解链→55℃下复性（引物与DNA模板链结合）→72℃下引物链延伸（形成新的脱氧核苷酸链）。下列有关PCR过程的叙述中不正确的是：  [ ]

A．变性过程中破坏了DNA分子内碱基对间的氢键，也可利用解旋酶实现

B．复性过程中引物与DNA模板链的结合是依靠碱基互补配对原则完成

C．延伸过程中需要DNA聚合酶、ATP、四种核糖核苷酸

D．PCR与细胞内DNA复制相比所需要酶的最适温度较高

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