Question

Make a schematic diagram for the phases of swallowing.

Answer 1

(a) oral preparatory phase; (b) oral transit phase; (c) pharyngeal phase; (d) esophageal phase.

The swallowing process is classified into oral, pharyngeal, and esophageal stages according to the location of the bolus.The oral stage is subdivided into oral preparatory and oral transit stages

Oral preparatory phase, in this phase, Food is chewed and mixed with saliva to form a bolus and bolus is positioned on the tongue for transport.

Oral transit phase, Once the bolus is prepared, the tongue begins the anterior to posterior propulsion of the bolus for passage to the pharynx

Pharyngeal phase, it consists of  propelling the food bolus through the pharynx,  airway protection, insulating the larynx and trachea from the pharynx during food passage to prevent the food from entering the airway.

Esophageal phase, upon entry of the bolus through the cricopharyngeal muscle, the esophageal phase is initiated,Esophageal propulsion begins via muscle contraction,Once the bolus has entered the esophagus, it is carried to the stomach by a mixture of esophageal peristalsis and gravity