试题与答案

DNA以半保留方式复制,如果一个具有放射性标记的双链DNA分子,在无放射性标记的环境

题型:单项选择题

题目:

DNA以半保留方式复制,如果一个具有放射性标记的双链DNA分子,在无放射性标记的环境中经过两轮复制。其产物分子的放射性情况如何()。

A.其中一半没有放射性

B.都有放射性

C.半数分子的两条链都有放射性

D.都不含放射性

答案:

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