•   the naso pharynx,
•   the oro pharynx and
•   the laryngo pharynx.
•   Oropharynx and laryngopharynx are associated with the alimentary tract
•   Food passes from the oral cavity to the pharynx and then into the oesophagus with which it is continuous.

• The lining membrane  is stratified squomous epithelium
• The middle layer - fibrous tissue - contains blood and lymph vessles and nerves
• The outer layer - a number of involuntery constrictor muscles which are involved in swallowing.

• Branches of the facial arteries
• Venous drainage : into the facial veins and the internal jugular veins

• Pharyngeal plexus and consists of parasmpathetic and sympathetic nerves
• parasympathetic : glossopharyngeal and vagus nerves
• Sympathetic from the cervical ganglia

• Eustachian Tube opening into the nasopharynx gets inflamed : eustachian catarrh; the pressure equilibrium between the external and internal ears is disturbed and the ear gets a blocked sensation.
• Retropharyngeal abscess produces a swelling in the back of the throat