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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).
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerRobert L. Cowie, MB, FCP(SA), MD, MSc, MFOM - Pulmonology
Current as ofAugust 21, 2015