Final answer:
The respiratory system contains mucus and cilia to clear large particles from the airway.
Step-by-step explanation:
The respiratory system contains various protective devices to clear large particles (>10 um) from the airway. The lungs produce mucus that traps particles, and the bronchi and bronchioles have cilia, hair-like projections that move the mucus and particles out of the airway. This mechanism is known as the mucociliary escalator, which moves the mucus and particles upward toward the throat, where they can be expelled from the body through coughing or clearing the throat.