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Identify the circumvallate papillae that create a v-shaped sulcus terminalis on the dorsal aspect of the tongue. At the base of the "v", identify the foramen cecum in the median plane of the tongue. The lingual tonsils are located at the base of the tongue near the epiglottis.
The v-shaped line of circumvallate papillae indicate the developmental divisions of the tongue, an anterior two-thirds and a posterior one-third. The anterior two-thirds of the tongue is innervated by the lingual nerve. The posterior third of the tongue is innervated by the glossopharyngeal nerve. Identify the distal course of the glossopharyngeal nerve. The distal portion of the glossopharyngeal nerve courses beneath the mucosa of the tonsillar fossa to reach the posterior third of the tongue.Links and References:
Grant's: 7.81-7.84
Netter: 52