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  • Dear gentlemen, SCIENCE has a confession.

  • Your life actually began as a female.

  • Well, phenotypically or physically speaking that is, though some prefer to call this stage gender neutral.

  • As you might know, when two people mate, they each combine half of their genetic information together; 23 chromosomes each.

  • One pair of these chromosomes helps to determine your sex.

  • If you're female, you contain two X chromosomes, one from your mother and one from your father, while males have one X and one Y chromosome.

  • At the moment of conception, you were of course male or female based on your genes but the Y chromosome doesn't kick in right away.

  • In fact, the first five to six weeks of embryonic development are attributed to the X chromosome alone, and females grow from embryo to fully developed to the influence of only the X chromosome.

  • So what does the Y chromosome do?

  • Once activated, one of the genes on the Y chromosome known as the SRY gene has two functions: to inhibit certain features of the X chromosome and to impose through dominance the physiological traits that a male must have.

  • The ovaries descend and become the testes, and the labia fuses to create the scrotum.

  • If you're a male, take a look.

  • Though it's more pronounced in some men than others, you'll likely notice a line or ridge of tissue on the scrotum, which is called the "scrotal raphe".

  • The skin of the scrotum and penis are zipped up like a zipper as the layers of cells develop in the embryo.

  • And the male variant of the clitoris?

  • Yep, that's the penis.

  • If the Y chromosome does not become activated for some reason, then the female phenotype or physical appearance will persist in a male.

  • Power added, this is also part of the reason males have nipples.

  • The nipples form before the activation of the Y chromosome and SRY gene and thus remain through development and life.

  • But, you don't develop breasts, sorry.

  • Got a burning question you want answered?

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Dear gentlemen, SCIENCE has a confession.

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C2 chromosome male female embryo activated gene

We were all female

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    可愛 posted on 2021/01/22
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