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问:我丈夫家是三代单传,婆婆一心想抱个孙子。听说我怀孕了,她不知从哪儿的江湖郎中手里,抓回了几包转胎药让我吃,说吃了就可使肚里的女孩变成男孩。请问是否真有转胎药?答:为了帮你彻底看清转胎药的真面目,先来看看胎儿性别是如何决定的吧。人类细胞的染色体有23对,其中22对为常染色体,1对为性染色体。男性性染色体为 XY,女性性染色体为 XX。精子在成熟分裂过程中由双倍体(46条)变成单倍体(23)条,产生两种精子:一种含 X 染色体,一种含 Y 染色体。卵子在成熟分裂过程中也由双倍体(46条)变成两个单倍体(23条),但所有的卵子均只含 X 染色体。在受精过程中,如果卵子与含 X 染色体的精子结合,孕卵的性染色体是XX,最终发育成女孩;若卵子与含 Y 染色体的精子结
Q: My husband’s family is three generations, mother-in-law wants to hug grandchildren. I heard that I was pregnant, she did not know where the rivers and lakes Langzhong hands, grabbed a few packets of tire drugs for me to eat, that eat can make the belly girl into a boy. Will there really tire transfer? A: In order to help you thoroughly see the true facets of fetal drugs, take a look at the fetal sex is how to decide it. There are 23 pairs of human cells chromosomes, of which 22 pairs of autosomal, 1 pairs of sex chromosomes. Male sex chromosome XY, female sex chromosome XX. Spermatozoa change from diploid (46) to haploid (23) during maturation, producing two sperms: one with the X chromosome and one with the Y chromosome. The egg also changed from diploid (46) to two haploids (23) during maturation, but all eggs contained only X chromosome. In the process of fertilization, if the egg and X chromosome containing sperm, the sex chromosome of the pregnant egg is XX, and eventually develop into a girl; if the egg and the Y chromosome sperm junction