The cells from the male and female that combine to form a zygote are called gametes. The main job of the gametophyte is gamete production. Gametes are haploid reproductive cells. Gametes are produced in the sex organs on the haploid gametophyte by mitosis or cellular division without reduction of chromosomes sets. There are two sex organs; archegonium which is found in the female sex organ producing egg cell and antheridium which is found in the male sex organ producing sperm cells.