下列有关生物变异的叙述，正确的是（）_刷题宝

题干

下列有关生物变异的叙述，正确的是（）

A：发生在真核细胞基因编码区的碱基改变，不一定会导致可遗传变异

B：无籽番茄是用秋水仙素处理番茄幼苗形成的，属于染色体变异

C：同源染色体的非姐妹染色单体之间局部交叉互换不会导致基因重组

D：基因突变和基因重组两者都能够丰富种群的基因库并改变基因频率

上一题下一题 0.0难度选择题更新时间:2014-01-13 07:24:34

答案(点此获取答案解析）

A

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