Introduction
- The oocyst is the resistant stage in the environment
- The infective sporozoite is released from the oocyst
- Inside the host, the sporozoites invade the intestinal epithelial tissue
- Sporozoites feed and grow
- As the sporozoite grows the nucleus divides forming a schizont
- The schizont contains numerous elongated merozoites
- The formation of merozoites is the first asexual reproductive stage called schizogony
- The schizont ruptures releasing the merozoites which also invade the epithelial cells
- Another generation of schizonts form which is the beginning of the sexual phase of reproduction called gametogony
- The merozoites form male microgamonts or female macrogamonts
- Collectively known as gamonts or gametocytes
- The microgamonts released from the microgametocyte penetrate and fertilise the macrogamont (which is contained within the macrogametocyte)
- Gametogony forms the zygote
- Surrounded by a cyst wall
- Forms the oocyst
- The oocyst is passed in the faeces and is unsporulated
- The oocyst becomes sporulated in the second asexual reproductive phase called sporogony
- Once the oocyst is sporulated it is infective