A musculomembranous tube extending from the base of the skull to the level of the sixth cervical vertebra, where it becomes continuous with the esophagus. It consists of an upper (nasopharynx), middle (oropharynx), and lower (laryngopharynx) portion. The pharynx communicates with the posterior nares (nose cavities), Eustachian tube, mouth, esophagus, and larynx. It provides a passageway for air from the nasal cavity to the larynx and for food from the mouth to the esophagus. It also acts as a resonating cavity.