why I look like this?

I’m a girl because my father has the one who decides my sex because the parents are the ones that apport sperm who has DNA and DNA contain chromosome that are the ones who put xx that means that I am going to be a girl if the nature wants that the kid is a boy the chromosome is gonna be xy. Each parent aport 23 chromosome (the mom in the ovun and the father in the sperm) so my father aport 23 chromosome in which he passed me physical appearance like: my nose, my ears, my mouth and my gestures, but my mother aport that 23 chromosome with my likes and feelings like:the movies, the food and clothes.

What causes the down syndrome?

The thing that causes down syndrome is a genetical disorder when the ovun and the sperm join that is call fertilization so the sperm and the ovun didn’t give 23 chromosome (that is the number of chromosome necesarys to have a healthier and well formed baby so that) so they give 21 chromosome so the baby cant not form all her body so his features are different and there mental capacity is different so they are more difficult to teach. But this problem is not of the fathers is a genetic disorder but anyone know the exactly problem, but the mothers that are younger than 18 years old and the ones that are older than 35 years old this are the mothers that can have the risks of having a baby with down syndrome.