CORE TOPIC:
Trachea (LP)

During inspiration, air is drawn first into the conducting passages of the upper respiratory tract, the nasal cavity, pharynx, larynx, trachea and bronchi. The structure and function of the upper respiratory tract is exemplified by this transverse section of the trachea.

The trachea is a rigid tube about 10 cm long. Embedded within the wall are between 16 and 20 C-shaped hyaline cartilages which maintain the patency of the airway. This is a section through one of the tracheal cartilages (stains pink). The trachea is the most anterior structure in the neck. The open ends of the cartilage would be in direct contact with the oesophagus. A bundle of smooth muscle fibres, the trachealis muscle, completes the circumference of the trachea. Trachealis muscle contracts during coughing reducing the diameter of the trachea and increasing the velocity of the air in forced expiration.

The conducting passages, including the trachea, are lined by respiratory epithelium.



Tutorial Navigator:
Core Supplementary Material on Trachea
Previous Topic

Next Topic 		trachea (MP) trachea LS (MP ) tracheal epithelium (HP)
Return to Respiratory System Main Index