Describe the role of saliva and the tongue in the oral cavity. Describe the process of swallowing. How is choking prevented?
In the oral cavity, saliva dissolves food and acts as a lubricant. It also begins the breakdown of starch via the enzyme amylase and contains agents which destroy the harmful microbes regularly introduced into the mouth. The tongue forms food into a ball-like mass of food, called a bolus, and, then, pushes it through the pharynx into the esophagus. This process, called swallowing, requires a complex set of reflexes to close off the trachea and nasal passages, which also empty into the pharynx, in order to prevent choking.
