The Lungs and Mucus
Mucus is vital to your lung's immune response because it traps irritants in the lungs and creates a protective barrier.
The Airways
Your airways, or respiratory tract, are a series of passages that air travels through to move into and out of your lungs. Your upper airways include nasal cavities, sinuses, the pharynx, and the larynx. Your lower airways are your trachea, bronchi, and bronchioles.
The Sinuses
The sinuses are four empty pockets lined with mucus membranes that help to trap and filter dust, germs, particles, and other irritants around us. These pockets drain out of the nose.