Apicomplexan life cycle

[1] Each stage in the life cycle of an apicomplexan organism is typified by a cellular variety with a distinct morphology and biochemistry.

After infecting a host cell, a trophozoite (see glossary below) increases in size while repeatedly replicating its nucleus and other organelles.

Organisms whose life cycles rely on this process include Theileria, Babesia,[4] Plasmodium,[5] and Toxoplasma gondii.

A merozoite (G. meros, part [of a series] +zōon, animal) is the result of merogony that takes place within a host cell.

A trophozoite (G. trophē, nourishment + zōon, animal) is the activated, intracellular feeding stage in the apicomplexan life cycle.

A hypnozoite (G. hypnos, sleep + zōon, animal) is a quiescent parasite stage that is best known for its "... probable association with latency and relapse in human malarial infections caused by Plasmodium ovale and P.

[13] A bradyzoite (G. bradys, slow + zōon, animal) is a sessile, slow-growing form of zoonotic microorganisms such as Toxoplasma gondii, among others responsible for parasitic infections.

In chronic (latent) toxoplasmosis, bradyzoites microscopically present as clusters enclosed by an irregular crescent-shaped wall (cysts) in infected muscle and brain tissues.

[14] A tachyzoite (G. tachys, fast + zōon, animal), contrasting with a bradyzoite, is a form typified by rapid growth and replication.

An oocyst (G. ōon, egg + kystis, bladder) is a hardy, thick-walled spore, able to survive for lengthy periods outside a host.