Haemozoin is a

Options

A. a precursor of hemoglobin
B. a toxin from Streptococcus
C. a toxin from Plasmodium species
D. a toxin from Haemophilus species

Answer

**Step-by-Step Solution:**

1. **Understanding Haemozoin**: Haemozoin is a substance that is produced as a result of the digestion of hemoglobin by certain blood-feeding parasites, particularly the Plasmodium species, which is responsible for malaria.

2. **Formation Process**: When these parasites feed on human blood, they break down hemoglobin, which is a protein found in red blood cells that carries oxygen. During this breakdown, the heme group (the non-protein part of hemoglobin) is released.

3. **Toxicity of Free Heme**: The free heme that is released during the digestion of hemoglobin is toxic to the parasites. To mitigate this toxicity, the parasites convert the free heme into a less harmful form known as haemozoin.

4. **Biocrystal Nature**: Haemozoin is characterized as a biocrystal. This means it has a crystalline structure and is a disposal product that helps the parasites avoid the harmful effects of free heme.

5. **Role of Haemozoin**: By producing haemozoin, the Plasmodium species can safely store the toxic byproduct of hemoglobin digestion, allowing them to survive and continue their lifecycle within the host.

6. **Conclusion**: Therefore, haemozoin is a toxin produced by the Plasmodium species as a result of the digestion of hemoglobin, serving as a means to detoxify the harmful free heme released during this process.

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