Larynx begins the lower respiratory tract and is closed by the epiglottis which prevents inspired air from entering the esophagus and food/fluid from entering the trachea; permits production of sounds.

The image to the right shows the basic structures of the larynx.

Examine the epithelium along this tissue

• Note the change from stratified squamous to pseudostratified, ciliated (or respiratory epithelium).
• The protrusion with the large mass of muscle represents one of the true vocal cords and the protrusion that consists mostly of areolar support tissue is an edge of a false vocal cord.
• Note the cartilage plates and skeletal muscles of the larynx and the thyroid gland tissue where the trachea begins.

Now for the trachea.