what are its functions?
It provides motor control of the extrinsic muscles of the tongue- genioglossus, hyoglossus, styloglossus, and the intrinsic muscles of the tongue.
Hypoglossal nerve
The hypoglossal nerve provides motor control of the extrinsic muscles of the tongue: genioglossus, hyoglossus, styloglossus, and the intrinsic muscles of the tongue. These represent all muscles of the tongue except the palatoglossus muscle. The hypoglossal nerve is of a general somatic efferent (GSE) type.
several cranial nerves innervate structures of the tongue Called the hypoglossal nerve
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Hypoglossal nerve [SEP] Function
The hypoglossal nerve provides motor control of the extrinsic muscles of the tongue: genioglossus, hyoglossus, styloglossus, and the intrinsic muscles of the tongue. These represent all muscles of the tongue except the palatoglossus muscle. The hypoglossal nerve is of a general somatic efferent (GSE) type. These muscles are involved in moving and manipulating the tongue. The left and right genioglossus muscles in particular are responsible for protruding the tongue. The muscles, attached to the underside of the top and back parts of the tongue, cause the tongue to protrude and deviate towards the opposite side. The hypoglossal nerve also supplies movements including clearing the mouth of saliva and other involuntary activities.