Anatomy and Physiology: The Respitory System

The Respitory System

It's interesting how many expressions we use that refer to the act of breathing: breathtaking, breathing life into something, and so on. Have you ever been swimming in the deep end and decided to swim down to get something shiny off the bottom of the pool, only to realize that you have been underwater just a bit too long, and that it's an awfully long way to the top! In moments like that, it becomes obvious how important breathing is! Despite that, breathing is so automatic that it usually escapes notice.

We all think about lungs when we think of breathing, but that is only the half of it! There is much more going on, and many safeguards to keep you from, well, dying! Of all the basic needs—food, water, air, and waste removal—lack of air, or the 21+ percent that contains oxygen anyway, is the fastest way to kick the bucket. Within minutes the lack of oxygen causes brain damage, and, ultimately, death. With all this urgency, there are many players involved, whose roles give you everything from life itself, to a voice all your own to express your thoughts.

Function Junction

A lot of people think the function of the respiratory system is just breathing. Nothing could be further from the truth. There are, in fact, six basic functions:

  • Exchanging gas between the air and the bloodstream, and also providing a surface area for that to happen (the respiratory surface).
  • Moving air in and out of the lungs.
  • Warming, humidifying, and filtering air before it reaches the respiratory surface.
  • Protecting the respiratory system from infection by pathogens.
  • Detecting air molecules and sending the message to the brain via the olfactory nerve—in a word: smelling.
  • Producing sound for speech, singing, and all that jazz …
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Excerpted from The Complete Idiot's Guide to Anatomy and Physiology © 2004 by Michael J. Vieira Lazaroff. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.

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