Cyanide poisoning will lead to

Options

A. Hypoxic hypoxia
B. Histotoxic hypoxia
C. Stagnant hypoxia
D. Anemic hypoxia

Answer

### Step-by-Step Solution:

1. **Understanding Cyanide**:
- Cyanide is a toxic compound produced by certain bacteria, fungi, and algae. It can also be found in various plants, where it is typically bound to sugar molecules as cyanogenic glycosides.

2. **Role of Cyanide in Plants**:
- In plants, cyanogenic glycosides serve a protective function, helping to defend against herbivores. This means that while cyanide is toxic to animals and humans, it has a role in plant defense mechanisms.

3. **Cyanide Poisoning**:
- When cyanide is ingested or inhaled, it leads to cyanide poisoning. This condition is classified as histotoxic hypoxia.

4. **Understanding Histotoxic Hypoxia**:
- Histotoxic hypoxia refers to a situation where the cells of an organism are unable to utilize oxygen effectively, despite its availability in the bloodstream.

5. **Mechanism of Action**:
- The primary reason for this inability to use oxygen is the inhibition of an essential enzyme known as cytochrome c oxidase. This enzyme plays a critical role in the electron transport chain during cellular respiration.

6. **Conclusion**:
- Therefore, cyanide poisoning leads to histotoxic hypoxia due to the inhibition of cytochrome c oxidase, preventing cells from using oxygen.

### Final Answer:
Cyanide poisoning will lead to histotoxic hypoxia.

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