Question

What is the primary function of Cranial Nerve 9 (Glossopharyngeal)?

a. Motor control of facial muscles
b. Taste sensation for the posterior third of the tongue
c. Visual perception
d. Hearing

Answer 1

Cranial Nerve 9, or the Glossopharyngeal nerve, is primarily responsible for taste sensation in the posterior third of the tongue as well as contributing to swallowing and saliva production.

Step-by-step explanation:

The primary function of Cranial Nerve 9 (Glossopharyngeal) is the sensory function that involves taste sensation for the posterior third of the tongue. This nerve also plays a role in contracting muscles in the tongue and throat which is essential for swallowing and the gag reflex, and is responsible for stimulating saliva production.

The glossopharyngeal nerve works in tandem with other nerves, such as the facial nerve, which handles taste sensations in the anterior two-thirds of the tongue, and the vagus nerve, which contributes to the gag reflex and various autonomic functions.