Diffusion of gases occurs in the alveolar region only and not in the other parts of respiratory system. Why?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Location of Gas Exchange**: The primary site for gas exchange in the respiratory system is the alveoli, which are tiny air sacs located at the end of the bronchioles in the lungs.

2. **Structure of Alveoli**: Alveoli are composed of a single layer of squamous epithelial cells. This thin structure facilitates easier diffusion of gases.

3. **Thin Barrier**: The barrier between the alveoli and the surrounding capillaries is very thin. This thinness allows for a more efficient exchange of oxygen and carbon dioxide between the air in the alveoli and the blood in the capillaries.

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