Symbiotic relationships refer to intimate associations between organisms of different species that provide a nutritional advantage. There are three main types: parasitism benefits the parasite at the host's expense, commensalism benefits one species without affecting the other, and mutualism benefits both species. Examples of each type are given.

1. Symbiotic Relationships - Parasitism - Commensalism - Mutualism SYMBIOSIS refers to relationships between organisms of DIFFERENT species that show an intimate association with each other Symbiotic relationships provide at least ONE of the participating species with a nutritional advantage 3 types of symbiosis have been recognised depending on the nature of the relationship:

10. The gametocytes are ingested by the female mosquito in a bloodmeal from an infected human. The gametocytes fuse to produce a zygote.The zygote secrete a cyst containing sporozoites formed from meiotic divisions

11. Sporozites enters the liver cell and during the next two weeks the intracellular parasite reproduces by mitosis within a liver cell to form as many as 200,000 merozoites! On maturation, the merozoites rupture the liver cells and are are released into the blood where they invade human red blood cells

12. In the red blood cells, the parasite matures asexually to produce another 10-20 merozoites which in turn can rupture the red blood cell and invade more liver cells or red blood cells

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