For life-threatening medical emergencies, call 911 without delay. For a mental health crisis, call or text 988 for free and confidential crisis support.
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.
Clinical Review Board All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
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