将大肠杆菌在含有15N标记的NH4NO3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1/16，则大肠杆菌的细胞_刷题宝

题干

将大肠杆菌在含有¹⁵N标记的NH₄NO₃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1/16，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

上一题下一题 0.0难度选择题更新时间:2018-11-27 11:43:17

答案(点此获取答案解析）

C

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