It is generally observed that malaria is rampant in area where construction work and/or stagnant water are usually seen. Plasmodium species are known to cause malaria. The parasite when injected by the mosquito into the human blood stream goes through specific life cycle stages. Select from below the correct sequence of stages

Options

A. Mosquito (sporozoites) `to` human liver (merozoitef `to` human RBC (gametes) `to` mosquito (zygote oocyst-sporozoites)
B. Mosquito (merozoites) `to` human RBC (gametes) human liver (sporozoites) `to` mosquito (oocyst zygote-sporozoites)
C. Mosquito (merozoites) `to` human liver (sporozoites `to` human RBC (gametes) `to` mosquito (oocyst zygote-sporozoites)
D. Mosquito (sporozoites) `to` human liver (sporozoites `to` human RBC (merozoites) `to` mosquito (zygote oocyst-sporozoites)

Explanation

To determine the correct sequence of life stages of the Plasmodium species that causes malaria, we can break down the process into distinct steps:

1. **Infection by Mosquito**: The life cycle begins when a female Anopheles mosquito bites a human and injects the Plasmodium parasite in the form of **sporozoites** into the bloodstream.

2. **Liver Stage**: The sporozoites travel to the liver, where they invade liver cells and undergo asexual reproduction, multiplying into **merozoites**.

3. **Blood Stage**: The merozoites are released back into the bloodstream, where they invade red blood cells. Inside the red blood cells, the merozoites continue to multiply and eventually rupture the cells, releasing more merozoites into the bloodstream.

4. **Gametocyte Formation**: Some of the merozoites develop into **gametocytes** (the sexual form of the parasite) within the red blood cells.

5. **Transmission to Mosquito**: When another female Anopheles mosquito bites an infected human, it ingests the gametocytes along with the blood.

6. **Sporozoite Formation**: Inside the mosquito, the gametocytes develop into gametes, which then fuse to form a zygote. The zygote develops into an **ookinete**, which then transforms into an **oocyst**. The oocyst eventually produces new sporozoites that migrate to the mosquito's salivary glands.

7. **Cycle Repeats**: When this mosquito bites another human, the cycle starts again with the injection of sporozoites.

**Correct Sequence of Stages**:
1. Sporozoites (injected by mosquito)
2. Merozoites (develop in liver)
3. Gametocytes (develop in blood)
4. Transmission to mosquito (when bitten)
5. Sporozoites (develop in mosquito)