XY XX

xx = female xy = male

There is no xxx or xxxy - if things worked that way you’d probably be an xxx…continued…

You don’t add the chromosomes - if an xx and an xy have an xy, then it’s just an xy…not an xxxy.

xx- female xy-male

Both have sex. The women automatically gives an x. The may can give a x or y. that is how you get boy or girl: mom x + dad y = xy boy, mom x + dad x = xx girl

You only get one from each parent because the sperm and egg cells (gamets) only have half the normal chromosome number

It is possible to have XXY or a single X or something similar but this is not normal, this is the result of something going wrong during meiotic cell division (called non-disjunction). This is how you get certain disorders like turners syndrome.