CHAPTER 1 3
Tongue and Taste
Gustation, taste, from the Latin gustare; related to gusto: enjoyment,
delight. The receptor cells that begin this process are located in the
mouth, primarily on the tongue, with a few on the upper palate and
the pharynx. They are grouped into clusters called taste buds. There
are approximately ten thousand taste buds in the human mouth, each
containing around a hundred taste receptor cells. That means we
have about one million taste receptor cells in our mouth. These cells
respond to molecules entering the mouth, most often components of
substances being consumed as food or drink.
Figure 13.1 depicts a taste bud and its component receptor cells in
the tongue. There is a pore exposing the receptor cells to the interior
of the mouth, where saliva dissolves the molecular components of
food and drink and swishes them about. The ends of the receptor cells
are composed of microvilli, filamentous structures that increase the
surface area exposed to tasty substances. Within the phospholipid bi-
layer membrane of the microvilli are taste receptor proteins.
Microvilli in taste cells and cilia in olfactory cells both serve to