Motile zygote of Plasmodium occurs in gut of female Anopheles. Zygote formed in stomach of mosquito about 9 to 10 days after sucking the blood of an infected human. Anopheles receives RBCs containing different stages of erthyrocytic cycle, including gametocyte. In its gut, all stages except the gametocytes are digested. The gametocytes remain unaffected by digestive enzymes of the mosquito, hatch out from the RBCs into the lumen of mosquito’s stomach and form sperm and ovum by gametogenesis. Syngamy or fusion of male and female gamete.