Last revised by Craig Hacking on 22 Feb 2024

The pharynx (plural: pharynges or pharynxes) is the superior dilated part of the alimentary tract that connects the nasal and oral cavities to the esophagus. It also forms part of the upper respiratory tract.

The pharynx is composed of three parts:

There are two groups of pharyngeal muscles, the external circular layer and the internal longitudinal layer.

The external circular layer is composed of the three pharyngeal constrictor muscles:

The internal longitudinal layer is composed of the three paired muscles:

Numerous branches anastomose in the pharynx, providing it with a rich arterial supply:

Veins of the same name drain either into the pterygoid venous plexus or directly into the internal jugular vein.

Most lymph drains back to the retropharyngeal nodes.

The muscles of the pharynx are supplied by the pharyngeal plexus, a network of nerves from pharyngeal branches of the vagus and glossopharyngeal nerves.

Sensory innervation is primarily from the glossopharyngeal nerve with a few notable exceptions:

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