Which stage of Plasmodium is infective for Mosquito

Options

A. Trophozoite
B. Gametocyte
C. Ookinete
D. Sporozoite.

Answer

To answer the question "Which stage of Plasmodium is infective for Mosquito?", we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding Plasmodium and its Life Cycle**:
- Plasmodium is a genus of protozoan parasites that cause malaria. The life cycle of Plasmodium involves two hosts: humans and female Anopheles mosquitoes.

2. **Identifying the Stages of Plasmodium**:
- In the life cycle of Plasmodium, there are several stages: sporozoites, merozoites, gametocytes, and the zygote (ookinete).

3. **Infective Stage for Humans**:
- The sporozoite stage is infective for humans. When a female Anopheles mosquito bites a human, it injects sporozoites into the bloodstream, which then travel to the liver and multiply.

4. **Infective Stage for Mosquito**:
- The question specifically asks for the infective stage for the mosquito. This stage is the ookinete. After the human host is infected, the merozoites released from red blood cells form gametocytes.

5. **Formation of Ookinete**:
- The microgametocytes undergo a process called exflagellation, leading to fertilization and the formation of a zygote. This zygote then develops into an ookinete, which is the infective stage for the mosquito.

6. **Penetration into Mosquito's Stomach**:
- The ookinete is a spindle-shaped, motile structure that penetrates the stomach wall of the mosquito, where it develops further into oocysts, eventually leading to the formation of new sporozoites.

7. **Conclusion**:
- Therefore, the infective stage of Plasmodium for the mosquito is the ookinete.

### Final Answer:
The infective stage of Plasmodium for the mosquito is the **ookinete**.

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