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. tracheitis Inflammation of the trachea. Tracheitis is usually caused by a viral infection and is aggravated by inhaled fumes, especially tobacco smoke. It often occurs with laryngitis and bronchitis in a condition known as laryngotracheobronchitis. Symptoms include a painful dry cough and hoarseness. In most cases, no treatment is needed.
The cartilage tube that brings air from the larynx to the two bronchi of the lungs. It is lined with mucus membranes and ciliated epithelia.
Popularly known as the windpipe, this tube extends from the LARYNX above to the point in the upper part of the chest, where it divides into the two large bronchial tubes, one to each lung (see LUNGS). It is about 10 cm (4 inches) in length and consists of a ?brous tube kept permanently open by about 20 strong, horizontally placed hoops of cartilage, each of which forms about two-thirds of a circle, the two ends being joined behind by muscle-?bres. This ?brocartilaginous tube is lined by a smooth mucous membrane, richly supplied with mucous glands and covered by a single layer of ciliated epithelium. (See also AIR PASSAGES.)
n. the windpipe: the part of the air passage between the *larynx and the main *bronchi, i.e. from just below the Adam’s apple, passing behind the notch of the *sternum (breastbone) to behind the angle of the sternum. The upper part of the trachea lies just below the skin, except where the thyroid gland is wrapped around it. —tracheal adj.
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