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Lung Disease & Respiratory Health Center

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Respiratory System


Illustration copyright 2000, 2004 by Nucleus Communications, Inc. All rights reserved.

The main function of the respiratory system is to supply the blood with oxygen in order for the blood to deliver oxygen to all parts of the body. The respiratory system does this through breathing.

The upper respiratory tract (upper airway) consists of the nose, mouth, sinuses, pharynx (upper section of the throat), and larynx (voice box). The lower respiratory tract consists of the trachea (windpipe), bronchial tubes, and lungs. The bronchial tubes carry air into the lungs and branch into smaller and smaller bronchioles. These end in alveoli (air sacs).

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerRobert L. Cowie, MB, FCP(SA), MD, MSc, MFOM - Pulmonology

Current as ofSeptember 9, 2014

WebMD Medical Reference from Healthwise

Last Updated: September 09, 2014
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.

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