The stage of Plasmodium falciparum infective to humans are formed in the

Options

A. liver of human
B. RBCs of mosquito
C. salivary glands of mosquito
D. intestine of human

Answer

To solve the question regarding where the infective stage of Plasmodium falciparum is formed, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Organism**: Plasmodium falciparum is a protozoan parasite that causes malaria, and it has a complex life cycle involving both humans and mosquitoes.

2. **Identify the Infective Stage**: The infective form of Plasmodium that enters the human body is known as sporozoites.

3. **Transmission Mechanism**: The sporozoites are transmitted to humans through the bite of an infected Anopheles mosquito.

4. **Life Cycle in Humans**: Once inside the human body, sporozoites travel to the liver, where they multiply. After this, they enter the bloodstream and infect red blood cells.

5. **Formation of Gametocytes**: In the human host, sexual stages of the parasite, known as gametocytes, are formed in the red blood cells.

6. **Mosquito's Role**: When a mosquito bites an infected human, it ingests the gametocytes along with the blood meal.

7. **Fertilization and Development**: Inside the mosquito's intestine, fertilization occurs, leading to the development of new forms of the parasite.

8. **Formation of Sporozoites**: The sporozoites, which are the infective forms, develop in the salivary glands of the mosquito.

9. **Conclusion**: Therefore, the correct answer to the question is that the infective stage of Plasmodium falciparum is formed in the salivary glands of the mosquito.

### Final Answer:
The stage of Plasmodium falciparum infective to humans is formed in the **salivary glands of the mosquito**.

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