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February 10, 2012

Lungs Design And Purpose (cont.)

Medical Reviewer:

What are other important events during the breathing cycle?

Outside air needs to be heated and moistened to match the body's temperature and humidity. As air passes down the tracheobronchial tree, it is warmed and water is added. Contaminants must also be removed. Nose hairs and tiny microscopic hairs called cilia, along with sticky mucus produced by the lining membrane help cleanse the air of impurities. Cilia beat in a synchronized fashion brushing any collected dirt and mucus up toward the mouth. The accumulated material is then coughed out or swallowed. By the time the air reaches the alveoli, it is virtually sterile. Amazingly, all of the above is occurring naturally while you are reading this information!

Lungs Design And Purpose At A Glance
  • The lungs exchange oxygen and carbon dioxide between the air we breathe and the blood.

  • The tracheobronchial tree is the passage way from the mouth to the interior of the lung.

  • Gas exchange occurs in the alveoli deep in the lungs.

  • Breathing air in (inhalation) requires muscular effort.

  • Air is warmed, humidified, and cleaned by the nose and lungs.

Last Editorial Review: 7/19/2007



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