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【单选题】
火鸡的性别决定方式是 ZW 型。曾有人发现少数雌火鸡 (ZW) 的卵细胞未与精子结合,也可以发育成二倍体后代。遗传学家推测,该现象产生的原因可能是:卵细胞与其同时产生的三个极体之一结合,形成二倍体后代 (WW 的胚胎不能存活 ) 。若该推测成立,理论上这种方式产生后代的雌雄比例是A.
雌︰雄 =1 ︰ 1
B.
雌︰雄 =2 ︰ 1
C.
雌︰雄 =3 ︰ 1
D.
雌︰雄 =4 ︰ 1
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