Protozoa - Apicomplexa Life Cycle

Generalized Apicomplexa Life Cycle

Apicomplexa life cycle has both Asexual and Sexual stages.

– Three distinct processes: sporogony, merogony, and gametogony.

Details & terminology vary between species

– In some species, all stages occur within a single host (monoxenous); other species involve multiple hosts (heteroxenous).

Key Terms

Sporogony = Asexual reproduction; produces sporozoites (“spore-like cells”)

Sporozoites = Invasive form; invade host cells and then go through merogony*

Mergonony = Asexual reproduction that produces merozoites (which have different names in different species!).

There can be multiple rounds of merogony, as merozoites reinvade cells and go through additional rounds of merogony.

Some merozoites can go through gametogony (aka, gametogenesis, aka, gamogony).
Gametogony is a sexually reproductive stage that produces male and female gametes.

This process includes formation of gamonts, then gamontocysts, which divide to form male and female gametes.

Male & Female Gametes fuse to form zygote.

Genetic recombination can occur here.

Zygotes go through sporogony, another asexual process that produces sporozoites

Some use "merogony" and "schizogony" interchangeably, whereas others use "schizogony" to include all three processes (merogony, sporogony, and gametogony).

Learn about the life cycle of Cryptosporidium

Protozoa - Apicomplexa Life Cycle

Related Tutorials