问题描述:
问题解答:
Aa Aa / \ / \ A(1) a(2) A(3) a(4) A(1)与A(3)形成AA 极核是AAA A(1)与a(4)形成Aa 极核是AAa a(2)与A(3)形成Aa 极核是Aaa a(2)与a(4)形成aa 极核是aaa
AAa or Aaa or AAA or aaa