Which nerve supplies circumvallate papillae of tongue?
High-Yield Explanation
Ans. A. Glossopharyngeal nerve. (Ref. BD Chaurasia, Anatomy, Vol 3, 2nd/pg.215).# Nerves which supply the sensation and taste of the tongue differ between the anterior and posterior parts.# Anteriorly, the sensation of taste is passed along the chorda tympani, a branch of the facial nerve. Sensation is passed along the lingual nerve, a branch of the trigeminal nerve.# Posteriorly, both taste and sensation are passed along the glossopharyngeal nerve.# All intrinsic and extrinsic muscles of the tongue are supplied by the hypoglossal nerve, with the exception of the palatoglossus. The palatoglossus is innervated by the vagus nerve.# Vallate papillae lie in front of sulcus terminalis, contain taste buds & glossopharyngeal nerve carries general & taste sensation from them & posterior 2/3rd of tongue.# Circumvallate papillae are present on anterior 2/3rd of the tongue, just in front of sulcus terminalis. They are supplied by glossopharyngeal nerve, which is the nerve of taste for posterior l/3rd of tongue.# Fungiform and filliform papillae are other papillae in tongue. Filiform Papillae are numerous on anterior 2/3rd of tongue & fungiform are scattered on sides & apex & both are supplied by lingual nerve (general sensations) & chorda tympani (taste).Tongue development: 1st and 2nd branchial arches form anterior 2/3 (thus sensation via CN V3, taste via CN VII). 3rd and 4th branchial arches form posterior 1/3 (thus sensation and taste mainly via CN IX, extreme posterior via CN X). Motor innervation is via CN XII. Muscles of the tongue are derived from occipital myotomes.Taste--CN VII, IX, X (solitary nucleus).Pain-CNV3, IX, X.Motor--CN XII.