ATTENTION

If you or someone you know is experiencing a mental health crisis, call 988 for 24/7 free and confidential crisis support. You do not have to be suicidal to call. Access more info and resources on suicide prevention, emotional and mental health support. 
toggle mobile menu Menu
toggle search menu

Site Navigation

Supplemental

Menu

Respiratory system

Top of the page

Respiratory system

Respiratory system, showing sinuses, pharynx, larynx, trachea, bronchial tubes, and lungs, with detail of bronchiole and alveoli.

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).

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

Current as of: August 6, 2023

Author: Healthwise Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Healthwise is a URAC accredited health web site content provider. Privacy Policy. How this information was developed to help you make better health decisions.

To learn more, visit Healthwise.org

© 1995- Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.

Your Partner in Health.

People are at the heart of great health care. That's why we are committed to delivering compassionate, high-quality care tailored to the communities we serve. 


Together with our community partners and patients, we're building a stronger, healthier future for all Idahoans.

Connect with Us
Contact Us In Boise (208) 381-2222