While heart disease deaths are declining, COPD is increasing rapidly. The pharynx is used by air and food, so epiglottis is a flap that keeps food from entering larynx. Trachea branches into two bronchi , one for each lung. Inside the lung, bronchi branch into smaller bronchioles .
Bronchioles end in small alveolar sacs .
These contain thousands of alveoli which are smaller sacs that take in oxygen from the bronchi and send to the pulmonary vein and the left atrium. They also take in carbon dioxide from the pulmonary artery and expell it through expiration. Caused by infection or irritation. Major concern with pharyngitis is not the disease, but consequences of not treating it. Occurs during sleep.