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respiratory tract

(RES-pih-ruh-TOR-ee trakt)
The organs that are involved in breathing. These include the nose, throat, larynx, trachea, bronchi, and lungs. Also called respiratory system.
Respiratory system anatomy; drawing shows the right lung with the upper, middle, and lower lobes, the left lung with the upper and lower lobes, and the trachea, bronchi, lymph nodes, and diaphragm. An inset shows the bronchioles, alveoli, artery, and vein.Enlarge this image in new window
Anatomy of the respiratory system showing the trachea, the right and left lungs and their lobes, and the bronchi. The lymph nodes and the diaphragm are also shown. Oxygen is inhaled into the lungs and passes through the alveoli (the tiny air sacs at the end of the bronchioles) and into the bloodstream (see inset), where it travels to the tissues throughout the body.
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