In heavy smoker the alveoli of the lungs are enlarged and damaged which reduces the surface area of the exchange of respiratory gases this condition is called

Options

A. asthma
B. silicosis
C. insominia
D. emphysema

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Condition**: The question describes a condition where the alveoli (air sacs in the lungs) are enlarged and damaged. This is a common issue among heavy smokers due to the harmful effects of smoking on lung tissue.

2. **Identifying the Effects**: The damage to the alveoli leads to a reduction in the surface area available for the exchange of respiratory gases (oxygen and carbon dioxide). This is critical because the larger the surface area, the more efficient the gas exchange.

3. **Recognizing the Medical Term**: The condition characterized by the enlargement and damage of alveoli, leading to decreased surface area for gas exchange, is known as emphysema.

4. **Differentiating from Other Conditions**:
- **Asthma**: A condition that causes narrowing of the airways, leading to difficulty in breathing, but does not primarily involve damage to the alveoli.
- **Silicosis**: A lung disease caused by inhaling silica dust, leading to inflammation and scarring, but not specifically characterized by enlarged alveoli.
- **Insomnia**: A sleep disorder, unrelated to lung function or gas exchange.

5. **Conclusion**: Based on the information provided, the correct answer to the question is **emphysema**. This condition is specifically associated with the damage and enlargement of the alveoli due to factors such as smoking.

**Final Answer**: The condition is called **emphysema**.

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