Hi there! Gender is a construct that developed when mankind created roles for the two sexes. It's less of a biological factor and more of a connection as to how someone feels they are as a person. You are thinking of sexual alignment, which is the physical counterpart. In fact, there *are* 3 sexes- the third being intersex, which is the state of having the parts of both sexes, give or take, which can come from mutation or be more likely through genetic inheritance. Open to sensible debate, I suppose, although it will take me a while to respond.
