题干

无尾猫是一种观赏猫。猫的无尾、有尾是一对相对性状,按基因的分离定律遗传。为了选育纯种的无尾猫,让无尾猫自交多代,但发现每一代中总会出现约1/3 的有尾猫,其余均为无尾猫。由此推断正确的是

A:猫的有尾性状是由显性基因控制的

B:自交后代出现有尾猫是基因突变所致

C:自交后代无尾猫中既有杂合子又有纯合子

D:无尾猫与有尾猫杂交后代中无尾猫约占12

上一题 下一题 0.0难度 选择题 更新时间:2019-11-18 08:46:50

答案(点此获取答案解析)

D

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