Arrange the following events of malarial infection in human beings sequentially:
(A) Transmission of gametocyte to female mosquito
(B) Gametocyte development in RBC
(C) Multiplication of parasite in RBC and rupturing of RBC
(D) Biting by female Anopheles mosquito and transmission of sporozoites
(E) Multiplication of parasite in liver cell
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (D), (E), (C), (B), (A)
A female Anopheles bites and injects sporozoites (D); they multiply in liver cells (E), then in red blood cells, which burst (C); gametocytes develop in the RBCs (B) and pass to a female mosquito when it bites (A).
NCERT Extract:
Common Diseases in Humans – “… 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, 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.”