How the lungs work

In order to learn what happens to the lungs during an asthma attack or pneumonia or COPD it is helpful to learn how the lungs work during a normal breath.

Nose - The nose serves a couple of functions other than sniffing. Hair and mucus in the nose help trap particles that may cause problems further down in the lungs. Air is also heated and humidified from traveling through the nose.

Trachea - The next major structure air passes through in its journey through the lungs is the trachea. The trachea is a conduit between the nose and the functional parts of the lungs.

Bronchi - Air leaving the trachea is next split into two different tubes called the bronchi. There is a right mainstem bronchi and a left mainstem bronchus. It is important to note that the right mainstem bronchi has a straighter path into the lungs than the left mainstem bronchi, due to the left lung accommodation of the heart.

Bronchioles - The breathing tubes further subdivide into smaller and smaller tubes. As this branching occurs the structure of the tubes change. Rings of cartilage which provide support to the larger breathing tubes become plates of cartilage which in turn become less and less prominent in the smaller tubes called bronchioles. Smooth muscle replaces the cartilage so that by the terminal bronchioles there is no cartilage just smooth muscle.

Alveoli - Alveoli are the functional parts of the of the lungs. These small sacks are thin, one cell thin to be exact and right behind them is a network of small capillaries. This makes it easy to exchange excess carbon dioxide with oxygen in the air.

Source - Human anatomy and Physiology published by John Wiley and Sons, Inc. Page 366.

 

 

Last Updated 11/30/2008 7:49:52 PM