Life cycle of Plasmodium (malaria)प्लाज़्मोडियम का जीवन-चक्र (मलेरिया)

NCERT Fig 7.1 · Class 12 Biology · Chapter 7 · interactive diagram

📖 Read Ch 7 with this diagram All diagrams

Parts and their functions

Female Anopheles mosquito (मादा एनाफ़िलीज़ मच्छर) — The vector (transmitting agent) of malaria and one of the two hosts of Plasmodium. Fertilisation and development of the parasite take place inside it.
Human host (मानव पोषक) — The second host. Here the parasite multiplies asexually — first in liver cells, then in red blood cells.
Sporozoites (स्पोरोज़ोआइट (बीजाणुज)) — The infectious form of Plasmodium. Stored in the mosquito's salivary glands and injected into a human with its bite.
Salivary glands (लार ग्रंथियाँ) — Mature sporozoites move here from the mosquito's intestine and are stored, ready to be injected at the next bite.
Liver cells (यकृत कोशिकाएँ) — Sporozoites first multiply asexually inside liver cells; the cells burst and release the parasites into the blood.
Red blood cells (RBCs) (लाल रुधिर कणिकाएँ (RBC)) — Parasites multiply asexually in RBCs and burst them; released parasites infect new RBCs. This repeats in cycles of fever.
Haemozoin (हीमोज़ोइन) — Toxic substance released when infected RBCs rupture; it causes the chill and high fever that recur every three to four days.
Gametocytes (युग्मकजनक (गैमीटोसाइट)) — Sexual stages that develop in red blood cells. A female Anopheles takes them up when it bites an infected person.
Mosquito's intestine (मच्छर की आँत) — Fertilisation and development of the parasite take place here; the sporozoites formed escape and migrate to the salivary glands.

Steps

1 · An infected female Anopheles bites: sporozoites enter the blood.
2 · Parasites multiply asexually in liver cells, then burst out into the blood.
3 · They multiply in RBCs and burst them: haemozoin → chill and fever every 3–4 days.
4 · Sexual stages (gametocytes) develop in RBCs.
5 · A female Anopheles bites the infected person and takes up gametocytes.
6 · Fertilisation and development take place in the mosquito's intestine.
7 · Sporozoites migrate to the salivary glands — ready for the next bite.

Original diagram drawn by Simple Learning Hub, based on NCERT Fig 7.1. Report a mistake