Malaria parasite completes its life-cycle in

Options

A. One host
B. Two host
C. Three host
D. Reservoir host

Explanation

**Step-by-Step Solution:**

1. **Identify the Malaria Parasite**: The malaria parasite is primarily known as Plasmodium, with Plasmodium falciparum being one of the most common and deadly species responsible for malaria in humans.

2. **Understand the Life Cycle**: The life cycle of the malaria parasite involves two hosts: the female Anopheles mosquito and the human host.

3. **Role of the Mosquito**: The mosquito serves as the vector for the malaria parasite. It carries the infective stage of the parasite, known as sporozoites. When a mosquito bites a human, these sporozoites are injected into the human bloodstream.

4. **Development in Humans**: Once inside the human body, the sporozoites travel to the liver, where they multiply and develop into merozoites. These merozoites then enter red blood cells (RBCs) and continue to multiply, leading to the symptoms of malaria.

5. **Formation of Gametocytes**: Some of the merozoites develop into gametocytes, which are the sexual forms of the parasite. These gametocytes are crucial for the next stage of the life cycle.

6. **Transmission Back to Mosquito**: When another mosquito bites an infected human, it ingests the gametocytes along with the blood. Inside the mosquito, these gametocytes undergo sexual reproduction to form new sporozoites.

7. **Storage in Mosquito**: The newly formed sporozoites migrate to the salivary glands of the mosquito, ready to be transmitted to another human host during the next bite.

8. **Conclusion**: Therefore, the malaria parasite requires two hosts to complete its life cycle: the human host and the mosquito host.

**Final Answer**: The malaria parasite completes its life cycle in two hosts: humans and mosquitoes.

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