精原细胞 娴细所 初级精母 细形6,XY)○ 初级卵母细胞 次级精 时细肥 精子 细胞 次级卵母 极体 23.x23,Y23,x123Y 细23 精子 极体 卵f conditions 1) maturation of oocyte 2) maturation of spermatozoon /ductus epididymus: 2-3 weeks, forward motility protein---conditions: 1) maturation of oocyte 2) maturation of spermatozoon: /ductus epididymus: 2-3 weeks, forward motility protein