Page 513 - Atlas of Histology with Functional Correlations

A cross section of a circumvallate papilla of the tongue is illustrated. The lingual

epithelium (2) that covers the circumvallate papilla is stratified squamous
epithelium (1). The underlying connective tissue, the lamina propria (3),
exhibits numerous secondary papillae (7) that project into the overlying
epithelium (1, 2) of the papilla. A deep trench, or furrow (5, 10), surrounds the
base of each circumvallate papilla.

The oval taste buds (4, 9) are located in the epithelium of the lateral
surfaces of the circumvallate papilla and in the epithelium on the outer wall of
the furrow (5, 10). (Fig. 13.9 illustrates the taste buds in greater detail with
higher magnification.)

Located deep in the lamina propria (3) and core of the tongue are numerous,
tubuloacinar serous (von Ebner) glands (6, 11), whose excretory ducts (6a,
11a) open at the base of the circular furrows (5, 10). The secretory product from
the serous acini (6b, 11b) produces solvents for taste-inducing substances.

Most of the core of the tongue consists of interlacing bundles of skeletal

muscles (12). Examples of skeletal muscle fibers sectioned in longitudinal
(12a) and transverse (12b) planes are abundant. This interlacing arrangement of
skeletal muscles (12) gives the tongue the necessary mobility for phonating and
chewing and swallowing of food. The lamina propria (3) surrounding the serous

glands (6, 11) and muscles (12) also contains an abundance of blood vessels (8).

FIGURE 13.7 ■ Tongue: circumvallate papilla (cross section). Stain:
hematoxylin and eosin. Medium magnification.

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