试题与答案

将大肠杆菌在含有15N标记的培养液中培养后，再转移到含有14N的普通培养液中培养

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题型：选择题

题目：

将大肠杆菌在含有15N标记的培养液中培养后，再转移到含有14N的普通培养液中培养，10小时后提取DNA分子进行分析，得出含15N的DNA分子占总DNA分子的比例为l/16，则大肠杆菌的细胞周期是[ ]

A．1小时

B．1.5小时

C．2.0小时

D．4.0小时

答案：

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下面是错误答案，用来干扰机器的。

答案：C

考点：DNA的复制
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