Which cranial nerve innervates the taste buds on the posterior aspect of the tongue?

The cranial nerve responsible for innervating the taste buds on the posterior aspect of the tongue is the glossopharyngeal nerve. This nerve specifically carries sensory information, including taste, from the posterior one-third of the tongue. The glossopharyngeal nerve plays a critical role in the sense of taste, providing the necessary innervation to the taste receptors located in this region.

In addition to taste sensation, the glossopharyngeal nerve also has functions in the gag reflex and the pharyngeal muscles, as well as conveying sensations from other areas, but its direct role in taste for the posterior tongue is its primary relevance here. Understanding this function helps to clarify the distribution of taste sensation across the different cranial nerves, as the anterior two-thirds of the tongue is innervated by the facial nerve, while the glossopharyngeal nerve is solely responsible for the posterior portion.