Intersexuality and How Sex is Determined

"If the Y [Male] chromosome is present in the embryo's cells, a gene within the short arm of the chromosome called SRY [SRY stands for sex-determining region of the Y chromosome] will turn on, initiating a chemical chain reaction that will turn on other genes and stimulate the production of male hormones[Testosterone]. If the X [Female] chromosome is present, or if the SRY [Sex determining region of the Male or Y chromosome] gene is missing from the Y [Male] chromosome, the embryo will develop into a female [Because the Sex Determing Region of the Male Chromosome is missing, a 'XY genetic male' - will develop into a 'XY biological female'] via mechanisms that are not fully understood."
(Read More) at PBS 'How is Sex determined?'
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