trachea

trachea (trāˈkēə) [key] or windpipe, principal tube that carries air to and from the lungs. It is about 41/2 in. (11.4 cm) long and about 3/4 in. (1.9 cm) in diameter in the adult. It extends from the larynx to the bronchial tubes and is situated in front of the esophagus (see respiration). The trachea consists of a supporting layer of connective and muscular tissue in which are embedded from 16 to 20 U-shaped rings of hard cartilage that encircle the front of the tube. Tiny hairs, or cilia, in the mucous membrane lining keep dust and other foreign particles from entering the lungs. The foreign material becomes trapped in the mucus and is swept by the beating cilia to the nose or mouth, where it is discharged from the body. The air tubes of insects and other arthropods are also called trachea.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.

More on trachea from Fact Monster:

  • Your Body's Systems - Systems of the body including circulatory, digestive, endocrine, immune, lymphatic, muscular, nervous, reproductive, respiratory, skeletal, and urinary.
  • windpipe - windpipe: windpipe: see trachea.
  • tracheotomy - tracheotomy tracheotomy , surgical incision into the trachea, or windpipe. The operation is ...
  • Erasistratus - Erasistratus Erasistratus , fl. 3d cent. B.C., Greek physician, b. Chios. He was the leader of a ...
  • croup - croup croup , acute obstructive laryngitis in young children, usually between the ages of three and ...

See more Encyclopedia articles on: Anatomy and Physiology