Swallowing
A programmed all-or-none reflex
Chewing and moving the bolus of food back is manly voluntary (striated muscle)
Pressure of bolus on pharynx triggers involuntary reflex (smooth muscle)
Tongue prevents food from moving back
Uvula elevated, sealing nasal passage
Larynx elevates and closure of glottis
Respiration briefly inhibited
Pharyngeal muscles force bolus back
Peristaltic waves move bolus through esophagus