Which stage of plasmodium parasite is infective for man?

Options

A. cryptomerozoite
B. Gametocyte
C. Sporozoite
D. Merozoite

Answer

To determine which stage of the Plasmodium parasite is infective for humans, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Plasmodium Life Cycle**:
- The Plasmodium parasite, responsible for malaria, has a complex life cycle that involves two hosts: the female Anopheles mosquito and humans.

2. **Identifying the Stages**:
- The life cycle of Plasmodium consists of two main phases: the sexual phase (in the mosquito) and the asexual phase (in humans).
- In the mosquito, the sexual phase produces sporozoites, which are the infective form of the parasite.

3. **Transmission to Humans**:
- The transmission of the Plasmodium parasite to humans occurs when a female Anopheles mosquito bites a human. During this bite, the mosquito injects saliva containing sporozoites into the human bloodstream.

4. **Infective Stage for Humans**:
- The sporozoite is the stage of the Plasmodium parasite that is infective for humans. Once inside the human body, the sporozoites travel to the liver, where they undergo asexual reproduction and eventually produce merozoites.

5. **Conclusion**:
- Therefore, the infective stage of the Plasmodium parasite for humans is the **sporozoite**.

### Final Answer:
The infective stage of the Plasmodium parasite for humans is the **sporozoite**.

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