Nasopharynx: The pharynx is a muscular structure lined with mucous membrane. It is divided into three parts: the nasopharynx, located behind the nasal cavities; the oropharynx located behind the oral cavity; and the hypopharynx (laryngopharynx), located behind and lateral to the larynx. The nasopharynx is considered part of the respiratory system. Lymphatics of the nasopharynx drain into submental, submandibular (submaxillary), and inter jugular (upper and lower deep cervical): jugulodigastric, jugulo-omohyoid, and retropharyngeal lymph nodes. The blood supply is via the external carotid arteries and internal jugular veins.