Final answer:
Cilia are the long hairs that filter air in the respiratory system.
Step-by-step explanation:
The structure of long hairs that filter air is called cilia. Cilia are microscopic extensions of the apical cell membrane that move fluids and trapped particles. In the respiratory system, cilia line the airway and form a mucociliary escalator that sweeps trapped particles upward towards the throat, where they can be expelled from the body.