How is a babys sex determined

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Sexual differentiation in humans is the process of development of sex differences in humans. In humans, biological sex is determined by five factors present at birth: the presence or absence of a Y chromosome, the Differentiation between the sexes of the sex organs occurs throughout embryological, fetal and later life.

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Description:Timing of Intercourse Studies indicate that the sperm with the X chromosome - or female chromosome - have a longer life span than the male sperm with the Y chromosome. Yet the male sperm appear to have a higher motility. Sperm motility is measured in two ways: Poor motility means the sperm have a difficult time swimming toward the egg. It is said that the sperm carrying the Y chromosome uses energy faster than the sperm carrying the X chromosome. The energy utilization is said to be due to the speed in which sperm swim.

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