The toxic effect of carbon monoxide is due to its greater affinity for haemoglobin as compared to oxygen approximately by

Options

A. 2 time
B. 20 times
C. 2000 times
D. 200-300 times

Answer

### Step-by-Step Solution:

1. **Understanding Carbon Monoxide (CO)**:
- Carbon monoxide is a colorless, odorless gas that is produced from incomplete combustion of carbon-containing fuels, metallurgical operations, and even naturally by plants and animals.

2. **Affinity for Hemoglobin**:
- Hemoglobin (Hb) is a protein in red blood cells that carries oxygen (O2) throughout the body.
- Carbon monoxide has a significantly higher affinity for hemoglobin compared to oxygen.

3. **Quantifying the Affinity**:
- Research indicates that carbon monoxide binds to hemoglobin approximately 200 times more tightly than oxygen does. This means that for every molecule of oxygen that can bind to hemoglobin, carbon monoxide can bind much more effectively.

4. **Formation of Carboxyhemoglobin**:
- When carbon monoxide binds to hemoglobin, it forms a stable compound known as carboxyhemoglobin. This compound prevents hemoglobin from carrying oxygen, which is crucial for cellular respiration and overall bodily function.

5. **Impact on Oxygen Transport**:
- The binding of carbon monoxide to hemoglobin impairs the transport of oxygen in the bloodstream. This can lead to various health issues such as headaches, decreased vision, and cardiovascular problems.

6. **Conclusion**:
- Therefore, the toxic effect of carbon monoxide is primarily due to its greater affinity for hemoglobin compared to oxygen, which is approximately 200 to 300 times greater.

### Final Answer:
The toxic effect of carbon monoxide is due to its greater affinity for hemoglobin as compared to oxygen approximately by 200 to 300 times.

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