Answer:
The reason that gametes are haploid is because neither parent has the full set of genetic information so each must contribute their half to make a whole. An organism has two sets of genes from their parents, half a set from the mother and the other from the father (1/2 + 1/2= 1). So together the information carried by the two haploid cells come together for an organism to form.
Hope this helps! God Bless!
