一个不含放射性元素的噬菌体,在脱氧核苷酸被32P标记及氨基酸被15N

一个不含放射性元素的噬菌体,在脱氧核苷酸被32P标记及氨基酸被15N标记的细菌内,连续增殖三代,子代噬菌体中含有32P15N的噬菌体分别占子代噬菌体总数的()

      A100%100%      B 25%50%       C   50%50%    D 25%0

答案

A

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