Figure 155

Diagram and photomicrograph of a taste bud. a. This diagram of a taste bud shows the neuroepithelial (sensory), supporting, and basal cells. One of the basal cells Is shown in the process of dividing. Nerve fibers have synapses with the neuroepithelial cells. (Based on Warwick R, Williams PL, eds. Cray's Anatomy. 35th ed. Edinburgh: Churchill Livingstone, 1973.) b. This high-magnification photomicrograph shows

Taste buds are present on fungiform, foliate, and circumvallate papillae

In histologic sections, taste buds appear as oval, pale-staining bodies that extend through the thickness of the epithelium (Fig. 15.5). A small opening onto the epithelial surface at the apex of the taste bud is called the taste pore. Three principal cell types are found in taste buds:

• Neuroepithelial (sensoiy) cells are the most numerous cells in the taste bud. These elongated cells extend from the basal lamina of the epithelium to the taste pore, through which the tapered apical surface of each cell extends microvilli (see Fig. 15.5). Near their apical surface they are connected to neighboring neuroepithelial or supporting cells by tight junctions. At their base they form a synapse with the processes of afferent sensory neurons of the facial (cranial nerve VII), glossopharyn-

the organization of the cells within the taste bud. The sensoiy and supporting cells extend through the full length of the taste bud. The apical surface of these cells contains microvilli. The basal cells are located at the bottom of the taste bud. Note that the taste bud opens at the surface by means of a taste pore. x640.

supporting cells

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