Which cranial nerve is involved in the taste sensation from the posterior one-third of the tongue?

The Glossopharyngeal Nerve, which is cranial nerve IX, is responsible for the taste sensation from the posterior one-third of the tongue. This nerve has a specific function in the taste perception pathway, as it innervates the taste buds located in that region.

Additionally, the Glossopharyngeal Nerve plays a role in other functions such as the sensory innervation of the oropharynx and stimulating the parotid salivary gland. This anatomical specialization highlights its importance in both taste and other sensory experiences in the throat area.

While the other nerves mentioned have significant functions, they do not specifically innervate taste sensations from the posterior one-third of the tongue. The Hypoglossal Nerve primarily controls tongue movements but does not contribute to taste perception. The Vagus Nerve is mainly involved in autonomic functions, including taste from the epiglottis and parts of the throat, but it does not serve the posterior tongue directly. The Facial Nerve is responsible for taste sensations from the anterior two-thirds of the tongue. Each cranial nerve has distinct roles, making the Glossopharyngeal Nerve the clear answer for taste sensation from the posterior part of the tongue.