Upon swallowing, food moves from the mouth directly into the oropharynx. Swallowing involves three stages; the oral phase where food is chewed and mixed with the saliva to form bolus, Pharyngeal phase where the vocals fold close to keep food and liquids from entering the airway, and the Esophageal stage where the bolus moves into the esophagus, the muscular tube that contracts to push the bolus into the stomach.