Swallowing is the process by which food from the mouth enters the oesophagus via the pharynx. It occurs in a specific sequence of phases to prevent food from entering the airway.

Oral phase

1. Mastication and moistening by saliva forms a soft and wet mass known as a bolus.
2. The tongue forms a longitudinal trough (mediated by intrinsic muscles) and then is pushed up against the hard palate to force bolus posteriorly.

Pharyngeal phase

1. Tensing and elevation of the soft palate closes (and protects) the nasopharynx
2. The pharynx is pulled upwards to receive the bolus
3. The oropharynx closed by palatoglossus and styloglossus to prevent food from re-entering mouth
4. Contraction of vestibular and vocal folds blocks the airway
5. The laryngeal inlet closes by elevation of the larynx via extrinsic muscles and contraction of the aryepiglotticus which flaps the epiglottis down like a lid.

Oesophageal phase

1. Once bolus reaches the oesophagus, elastic coil resets the epiglottis and elevated larynx, opening laryngeal inlet to resume respiration.
2. Oesophageal peristalsis sends bolus into the stomach