Anatomy of the tongue Flashcards
What vertebral level is the hyoid bone located at?
C3.
What does the hyoid do during swallowing?
It is elevated and lifts the entire pharynx up. The tongue then pushes the food bolus down.
What are the four extrinsic muscles of the tongue?
Genioglossus
Hyoglossus
Styloglossus
Palatoglossus
What is they only extrinsic tongue muscle not innervated by the hypoglossal nerve?
The palatoglossus. This is because it is derived from pharyngeal arch 4 and is therefore innervated by the vagus nerve.
What is the origin and insertion of the genioglossus?
It originates on the mandible (same spot as the geniohyoid) and inserts into the entire dorsum of the tongue.
What is the function of the genioglossus?
It unilaterally deviates the tongue to the contralateral side (right genioglossus will push the tongue to the left, ect) and bilaterally protrudes the tongue.
What is the origin and insertion of the hyoglossus?
It originates on the hyoid bone and inserts on the side of the tongue.
What is the function of the hyoglossus?
It acts to retract and depress the tongue.
What is the origin and insertion of the styloglossus?
It originates on the styloid process and inserts on the side of the tongue.
What is the function of the styloglossus?
It acts to retract and elevate the tongue.
What is the origin and insertion of the palatoglossus?
It originates on the soft palate and inserts on the side of the tongue.
What is the function of the palatoglossus?
It serves to pull the tongue and the soft palate together.
What is the sensory innervation of the epiglottic portion of the tongue?
Both taste and sensation are from the vagus nerve (CN X).
What is the sensory innervation of the root of the tongue (posterior 1/3)?
Both taste and sensation are from the glossopharyngeal nerve (CN IX).
What is the sensory innervation of the body of the tongue (anterior 2/3)?
Taste is via the chorda tympani (facial nerve) while sensation is from the lingual nerve (CN V3).
