WebMD
Font Size
A
A
A

Gas exchange in the lungs

Illustration copyright 2000 by Nucleus Communications, Inc. All rights reserved. http://www.nucleusinc.com

In the lungs oxygen and carbon dioxide (a waste product of body processes) are exchanged in the tiny air sacs (alveoli) at the end of the bronchial tubes. The alveoli are surrounded by capillaries. When a person inhales, oxygen moves from the alveoli to the surrounding capillaries and into the bloodstream. At the same time, carbon dioxide moves from the bloodstream to the capillaries and into the alveoli. The carbon dioxide is removed from the lungs when a person exhales.

Primary Medical Reviewer Renée M. Crichlow, MD
- Family Medicine
Primary Medical Reviewer Kathleen Romito, MD
- Family Medicine
Specialist Medical Reviewer Ken Y. Yoneda, MD
- Pulmonology
Last Updated June 16, 2006

WebMD Medical Reference from Healthwise

Last Updated: June 16, 2006
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
@ 1995-2007, Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.