When chromosomes do not separate you end up with a gamete with to many or to few chromosomes. This is known
as...

The phenomenon of unequal separation in meiosis is called nondisjunction. If nondisjunction causes a missing chromosome in a haploid gamete, the diploid zygote it forms with another gamete will contain only one copy of that chromosome from the other parent, a condition known as monosomy. I think sorry if wrong ;)

answerbacterium;