In protozoans reproduction is sexual or asexual. The most frequent form of sexual reproduction is binary division, or scissiparity, in which the cell divides itself by mitosis originating two daughter cells. Some species, like the plasmodium, agent of malaria, reproduce asexually by schizogony (multiple fission); in this form of reproduction the cell becomes multinucleated, generally inside a host cell, and each nucleus is expelled out together with cytoplasm portions giving rise to new protozoans.
The sexual reproduction in protozoans can happen by conjugation, with incorporation of genetic material from one cell into another, or by gametes that fecundate others and form zygotes. In the plasmodium sexual reproduction happens in the mosquito, the definitive host, and the zygote undergoes mitosis (sporogony) creating many sporozoites.
