The words "respiratory" and "respiration" refer to the lungs and breathing.
Lungs - illustration
Upper respiratory tract - illustration
Upper respiratory tract
Lower respiratory tract - illustration
Lower respiratory tract
Review Date: 11/6/2012
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.