Figure 2 - Lateral view of bolus propulsion during swallowing.

a: Voluntary initiation of the swallow by tongue "loading." b: Bolus propulsion by tongue dorsum and UES opening anticipating bolus arrival. c: Bolus entry into the pharynx associated with epiglottal downward tilt, hyolaryngeal excursion, and UES opening. d, e: Linguapharyngeal contact facilitating bolus passage through (d) the pharynx and (e) the UES, and completion of oropharyngeal swallowing. Then the entire bolus is on the esophagus. (Source: Netter medical illustration used with permission of Elsevier.)