Why is smoking related to emphysema?

Explanation

**Step-by-Step Solution:**

1. **Understanding Emphysema**: Emphysema is a chronic lung condition that affects the alveoli, the tiny air sacs in the lungs where gas exchange occurs. In emphysema, the walls of the alveoli become damaged and lose their elasticity.

2. **Role of Smoking**: Smoking introduces harmful chemicals into the lungs. These chemicals can cause repeated irritation to the lung tissues, particularly the alveoli.

3. **Irritation Leads to Inflammation**: The continuous irritation from smoking leads to inflammation in the lungs. Inflammation is the body's response to injury or irritation, and it can cause swelling and damage to the lung tissues.

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