Toxic haemozoin that causes malarial fever is formed from host

Options

A. DNA
B. RNA
C. Protein
D. carbohydrates.

Answer

To answer the question, "Toxic haemozoin that causes malarial fever is formed from host," we need to understand the lifecycle of the Plasmodium species, particularly Plasmodium vivax, and how it interacts with the human host.

### Step-by-Step Solution:

1. **Introduction of Plasmodium**: The lifecycle of Plasmodium begins when a female Anopheles mosquito bites a human, injecting the infective stage known as the sporozoite into the bloodstream.

2. **Entry into the Liver**: After entering the bloodstream, the sporozoites travel to the liver, where they undergo asexual reproduction through a process called multiple fission. This stage is crucial for the multiplication of the parasite.

3. **Invasion of Red Blood Cells (RBCs)**: Once the sporozoites mature in the liver, they enter the red blood cells. Inside the RBCs, they develop through several stages, starting with the trophozoite stage.

4. **Trophozoite Stage**: The trophozoite grows by feeding on the cytoplasm of the RBCs. As it matures, it undergoes changes, including the formation of a contractile vacuole.

5. **Formation of Hemozoin**: During the breakdown of hemoglobin (the protein in RBCs that carries oxygen), the trophozoite produces granules known as hemozoin. These granules are a byproduct of hemoglobin digestion.

6. **Toxicity and Fever**: Hemozoin is toxic and acts as a pyrogen, which means it can induce fever. The release of hemozoin occurs every 48 to 72 hours as RBCs break down, leading to intermittent fever in malaria patients.

7. **Conclusion**: Therefore, the toxic hemozoin that causes malarial fever is formed from the breakdown of hemoglobin in the host's red blood cells.

### Final Answer:
The toxic hemozoin that causes malarial fever is formed from **hemoglobin** in the host's red blood cells.

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