The life cycle of Plasmodium.

The life cycle of Plasmodium. 
  • Plasmodium enters the human body as sporozoites (infectious form) through the bite of infected female Anopheles mosquito. 
  • The parasites initially multiply within the liver cells and then attack the red blood cells (RBCs) resulting in their rupture. 
  • The rupture of RBCs is associated with release of a toxic substance (by merozoits), haemozoin, which is responsible for the chill and high fever recurring every three to four days. 
  • When a female Anopheles mosquito bites an infected person, these parasites enter the mosquito’s body and undergo further development. 
  • The parasites multiply within them to form sporozoites that are stored in their salivary glands.
  • When these mosquitoes bite a human, the sporozoites are introduced into his/ her body, thereby initiating the events mentioned above. 
  • It is interesting to note that the malarial parasite requires two hosts (digenetic) – human (secondary) and mosquitoes (primary) – to complete its life cycle; the female Anopheles mosquito is the vector (transmitting agent) too.
The life cycle
  • Gametogony
  • Sporogony
  • Schizogony (liver- preerythrocytic cycle & RBC- erythrocytic cycle)
              Erythrocytic phase of Plasmodium vivax is c toppr.com


Asexual life form
sporozoite>cryptozoite>metacryptozoit>trophozoite>signet ring>amoeboid>schizont>merozoite




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