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当前学科:生物化学
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一种突变细菌从群落形态学(即表型)不能与其野生型相区别,这一突变可能是()
A . A、一个点突变
B . B、一个无义突变或错义突变
C . C、密码子第三个碱基的替换
D . D、A和C
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