The air passage, also called the windpipe, that runs from immediately below the larynx to behind the upper part of the sternum, where it divides to form the bronchi. The trachea is made of fibrous and elastic tissue and smooth muscle. It also contains about 20 rings of cartilage, which keep it open. The lining of the trachea has cells (goblet cells) that secrete mucus and cells with cilia, which beat the mucus upwards to help keep the lungs and airways clear.
Trachea |
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