Which nerve carries taste from the posterior third of the tongue?

Which nerve carries taste from the posterior third of the tongue?

• A. Facial (VII)
• B. Hypoglossal (XII)
• C. Glossopharyngeal (IX)
• D. Vagus (X)

Answer: (C)

Taste from the posterior third of the tongue is carried by the glossopharyngeal nerve. This nerve provides the special visceral afferent supply for taste in that area, with the fibers traveling to the brainstem's solitary nucleus for processing. The other nerves don’t supply taste to this region: the facial nerve handles taste from the anterior two-thirds (via the chorda tympani), the hypoglossal nerve is responsible for motor control of tongue muscles, and the vagus carries taste from the epiglottis and nearby areas rather than from the posterior tongue.

Taste from the posterior third of the tongue is carried by the glossopharyngeal nerve. This nerve provides the special visceral afferent supply for taste in that area, with the fibers traveling to the brainstem's solitary nucleus for processing. The other nerves don’t supply taste to this region: the facial nerve handles taste from the anterior two-thirds (via the chorda tympani), the hypoglossal nerve is responsible for motor control of tongue muscles, and the vagus carries taste from the epiglottis and nearby areas rather than from the posterior tongue.