What is the role of cilia in the respiratory tract?

Explanation

**Step-by-Step Solution:**

1. **Definition of Cilia**: Cilia are small, hair-like projections that are found on the surface of certain cells. They are capable of movement.

*Hint: Remember that cilia are not just static structures; their movement is crucial for their function.*

2. **Location in the Respiratory Tract**: In the respiratory tract, particularly in the conducting zone, cilia are found on ciliated columnar epithelial cells. This area includes parts like the trachea and bronchi.

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