Page 664 - Atlas of Histology with Functional Correlations

Extending from the bases of the olfactory cells (4) are axons that pass into

the lamina propria (6) as bundles of unmyelinated olfactory nerves, or fila
olfactoria (14). The olfactory nerves (14) leave the nasal cavity and pass into the
olfactory bulbs at the base of the brain.

The transition from the olfactory epithelium (1) to the respiratory epithelium
(9) is abrupt. The respiratory epithelium (9) is a pseudostratified columnar

epithelium with distinct motile cilia (10) and numerous goblet cells (11). Also,
the height of the respiratory epithelium (9) is similar to that of the olfactory
epithelium (1). In other regions of the tract, the respiratory epithelium (9) is
reduced in comparison to the olfactory epithelium (1).

The lamina propria (6) contains capillaries, lymphatic vessels, arterioles (8),
venules (13), and branched, tubuloacinar serous olfactory (Bowman) glands
(7). The olfactory glands (7) deliver their secretions through narrow excretory
ducts (12) that penetrate the olfactory epithelium (1). The secretions from the
olfactory glands (7) moisten the epithelial surface, dissolve the molecules of

odoriferous substances, and stimulate the olfactory cells (4).

FIGURE 17.5 ■ Olfactory mucosa: details of a transitional area. Stain:

hematoxylin and eosin. High magnification.

FIGURE 17.6 | Olfactory Mucosa in Nose:

Transition Area

In the superior region of the nasal cavity, the respiratory epithelium changes
abruptly into the olfactory epithelium, as shown in this higher-power

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