试题与答案

超亲遗传与杂种优势有何异同?

题型:问答题 简答题

题目:

超亲遗传与杂种优势有何异同?

答案:

参考答案:

后代超越双亲的遗传现象,这就是超亲遗传和杂种优势的相似处。

它们的不同点是:

①前者更多的是单个数量性状的遗传,后者是综合性状;

②前者出现于杂种二代及以后各世代而后者在杂种一代最强,在F2代及以后的世代减弱;

③前者是由基因型纯合导致,后者是由基因型杂合导致;

④前者涉及基因累加效应,能稳定遗传;而后者涉及非累加效应,不能稳定遗传。

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