Question

Which cranial nerve provides taste to the posterior 1/3rd of the tongue?

1) Facial nerve (CN VII)
2) Glossopharyngeal nerve (CN IX)
3) Hypoglossal nerve (CN XII)
4) Vagus nerve (CN X)

Answer 1

The Glossopharyngeal nerve (CN IX) provides taste to the posterior 1/3rd of the tongue.

Step-by-step explanation:

The cranial nerve that provides taste to the posterior 1/3rd of the tongue is the Glossopharyngeal nerve (CN IX).

Once the gustatory cells in the taste buds are activated by taste molecules, they release neurotransmitters onto the dendrites of sensory neurons. These neurons are part of the glossopharyngeal cranial nerve which connects to taste buds in the posterior two-thirds of the tongue. The glossopharyngeal nerve also relays general sensations from the pharyngeal walls.

Therefore, the Glossopharyngeal nerve (CN IX) is responsible for taste in the posterior 1/3rd of the tongue.