Infectious form of plasmodium for humans is:-

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the infectious form of Plasmodium that affects humans. Plasmodium is a genus of parasitic protozoa.

2. **Understand the Disease**: Plasmodium is known to cause malaria, which is a significant disease affecting millions of people worldwide.

3. **Know the Species**: There are several species of Plasmodium that can infect humans. The main species include:
- Plasmodium malariae
- Plasmodium vivax
- Plasmodium ovale
- Plasmodium falciparum

4. **Transmission Vector**: The transmission of Plasmodium to humans occurs through a specific vector, which is the female Anopheles mosquito.

5. **Infectious Form**: The infectious form of Plasmodium that is transmitted to humans is the **sporozoite**. This is the stage of the parasite that is injected into the human bloodstream when an infected mosquito bites.

6. **Life Cycle Understanding**: In the life cycle of Plasmodium, sexual reproduction occurs in the mosquito (the definitive host), while asexual reproduction occurs in humans (the intermediate host).

7. **Conclusion**: Therefore, the infectious form of Plasmodium for humans is the **sporozoite**.

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