What Features of the Respiratory System Protect Us from Infection

Question

What features of the respiratory system protect us from infection?
A)Nasal hairs
B)Cilia
C)Mucus
D)Macrophages
E)All of the choices are correct.

Accepted Answer

All of the features listed (nasal hairs, cilia, mucus, and macrophages) help protect us from infection. Nasal hairs and mucus trap pathogens before they can enter the respiratory system, while cilia move the mucus and trapped particles out of the respiratory tract. Macrophages are immune cells that engulf and destroy pathogens that make it past the other respiratory defenses. Together, these features help prevent infection and keep our respiratory system healthy.