Question

CN IX (glossopharyngeal) provides motor innervation to the stylopharyngeus muscle. What is the function of CN IX?

1) Motor innervation to the stylopharyngeus muscle
2) Sensory innervation to the posterior third of the tongue
3) Motor innervation to the muscles of the pharynx
4) Sensory innervation to the pharynx and tonsils

Answer 1

CN IX (glossopharyngeal) provides motor innervation to the stylopharyngeus muscle, sensory innervation to the posterior third of the tongue, and sensory innervation to the pharynx and tonsils.

Step-by-step explanation:

The function of CN IX (glossopharyngeal nerve) is to provide motor innervation to the stylopharyngeus muscle. It is also responsible for sensory innervation to the posterior third of the tongue, as well as sensory innervation to the pharynx and tonsils. Additionally, the glossopharyngeal nerve is involved in taste perception and saliva production.