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X like X chromosome:
“X is the sex chromosome found twice in normal females = XX and once, along with a Y chromosome, in normal males = XY.”
The X chromosome carries hundreds of genes (informations about how you are going to be). Few, if any, of them have anything to do with sex.
The inheritance of genes on the X follows special rules because males have only a single X chromosome, and genes on the X are expressed in males.
Genes inherited in this manner are said to be sex-linked or, more precisely, X-linked. An example is Hemophilia A and hemophilia B.
A boy with hemophilia is Xh Y (the h is the hemophilia gene) and the carrier of hemophilia which is a woman will be XhX.
Sometimes both X in a woman can have the gene of hemophilia…this is very rare and is due to A MUTATION in the other X chromosome or in both. We have cases as I wrote in an old post, of women with hemophilia.