Which is the infective stage for mosquito in case of plasmodium vivax:

Ans. (a) Gametocyte Infective forms for human is sporozoites in saliva of mosquito Infective forms for mosquito is gametocytes in human blood. At least 12 gametocytes per cubic mm of blood must be present to infect mosquito. Gametocytes are maximum in number during the early stages of infections (may exceed 1000 per cubic mm of blood). Nonmotile zygote conveed into motile ookinete in about 18 - 24 hours.