Why do we often sneeze when we inhale a lot of dust-laden air?

Explanation

**Step-by-Step Solution:**

1. **Inhalation of Dust-Laden Air**: When we breathe in air that contains a lot of dust particles, these particles can enter our respiratory system through the nose.

2. **Nasal Hair Function**: The nose has tiny hair-like structures called cilia that help trap dust and other foreign particles. Normally, these hairs prevent most dust from entering deeper into the respiratory system.

3. **Excess Dust Particles**: When there is an excessive amount of dust in the air, some particles can bypass the nasal hairs and reach the nasal cavity.

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