The trachea or windpipe is a 4-5 inch (10-12 cm) tube that runs through the
lower neck and chest just anterior to the esophagus. It functions to conduct
air between the larynx and primary bronchi.
In the wall of the trachea are 16 to 20 hyaline cartilage rings. They stiffen
the wall so that the 1 inch (2.5 cm) tracheal lumen stays open and air flows
unimpeded.
