9CaKrnQgPa3作者:health.huanqiu.comgallery胎儿性别形成的全过程/e3pmt7dq2/e3pn6gvs71356912480000责编:xuaifang环球网健康社区135691248000011["9CaKrnQgJex","9CaKrnQgJgU","9CaKrnQgJi2","9CaKrnQgJ7D"]{"gallery":{"members":[{"desc":" 胎儿的性别是怎么形成的?或者说胎儿的性别是怎样被决定的呢?胎儿的生殖器官如何分化发育?一起来了解胎儿性别的形成过程以及确定胎儿性别的时间和方式!\r\n","url":"\/\/himg2.huanqiucdn.cn\/attachment2010\/2012\/1227\/20121227060842535.jpg"},{"desc":" 胎儿是由卵子和精子结合而形成的新生命。正常女性一个月经周期排一个卵,卵子的性染色体都是一样的,都是X染色体。而精子内的性染色体,则有两种类型:一种是带X染色体精子(通称X染色体精子或X精子);一种是带Y染色体的精子(通称Y染色体精子或Y精子)。\r\n\r\n","url":"\/\/himg2.huanqiucdn.cn\/attachment2010\/2012\/1227\/20121227060847964.jpg"},{"desc":" 如果进入卵子的精子是X染色体精子,和其结合形成的受精卵就是XX性染色体,即为女胎;\r\n","url":"\/\/himg2.huanqiucdn.cn\/attachment2010\/2012\/1227\/20121227060852333.jpg"},{"desc":" 如果进入卵子的精子是Y染色体精子和其结合形成的受精卵则为XY性染色体,即形成男胎。所以胎儿性别完全由男性的精子决定。\r\n","url":"\/\/himg2.huanqiucdn.cn\/attachment2010\/2012\/1227\/20121227060852611.jpg"},{"desc":" 在性交时,一次射入阴道几亿个精子。\r\n","url":"\/\/himg2.huanqiucdn.cn\/attachment2010\/2012\/1227\/20121227060852170.jpg"},{"desc":" Y精子数量占极大优势,是X精子的二倍,但到了最后,Y精子的数量和X精子的数量相差无几或更少。\r\n","url":"\/\/himg2.huanqiucdn.cn\/attachment2010\/2012\/1227\/20121227060852866.jpg"},{"desc":" X精子或Y精子和卵子结合完全是随机的,应该说各有50%的可能性,所以生男生女基本上是相等的。\r\n\r\n","url":"\/\/himg2.huanqiucdn.cn\/attachment2010\/2012\/1227\/20121227060852457.jpg"},{"desc":" 不过,X精子和Y精子在外观和性能方面都是有区别的。\r\n","url":"\/\/himg2.huanqiucdn.cn\/attachment2010\/2012\/1227\/20121227060852532.jpg"}]}}//himg2.huanqiucdn.cn/attachment2010/2012/1231/20121231091012386.jpg