How do the protective mechanisms present in the respiratory tract help prevent diseases from developing?

Question

Dylan Andrews · Accepted Answer

By preventing the virus from reaching the lungs, where it can infect the body.

The trachea and bronchi are lined with a layer of mucus in order to trap pathogens and bar them from reaching the lungs. This mucus is then moved up the airway by the cilia of cells in the trachea to be coughed up or swallowed.

Here's a diagram of the cilia in the trachea:

The nasal cavity also has mucus in addition to hair to trap pathogens before they reach the lungs.

As a last line of defense, there are macrophages (white blood cells) present on the alveoli in the lungs to swallow up any pathogens that got past the mucus/hair defense.

Dylan Andrews · Answer

undefined The protective mechanisms in the respiratory tract include mucus production, cilia movement, cough reflex, and immune cells like macrophages. Mucus traps particles and pathogens, while cilia move them towards the throat to be swallowed or expelled. The cough reflex expels irritants, and immune cells in the respiratory tract neutralize pathogens. Together, these mechanisms prevent pathogens from entering deeper into the lungs and causing diseases.