Page 666 - Atlas of Histology with Functional Correlations

through the ethmoid bone in the skull and synapse in the olfactory bulbs of

the brain located in the skull above the nasal cavity. From here, neurons relay
the information to the cortex of the brain for odor interpretation.

Olfactory epithelium is kept moist by a watery secretions produced by
serous olfactory (Bowman) glands located below the epithelium in the
lamina propria. This secretion, delivered via ducts through the olfactory

epithelium, continually washes the surface of olfactory epithelium. In this
manner, odor molecules are trapped, dissolved, and then washed away by the
new fluid, allowing the receptor cells to detect and respond to new odorants.

The supportive cells form junctional complexes with the adjacent

olfactory cells to provide structural support. Basal cells serve as stem cells
and can give rise to new olfactory cells and supportive cells of the olfactory
epithelium.

FIGURE 17.7 | Epiglottis (Longitudinal Section)

The epiglottis is the superior portion of the larynx that projects upward from the
larynx’s anterior wall. It has both a lingual and a laryngeal surface.

A central elastic cartilage forms the framework of the epiglottis (3). Its
lingual mucosa (2) (anterior side) is lined with a stratified squamous

nonkeratinized epithelium (1). The underlying lamina propria merges with the
connective tissue perichondrium (4) of the elastic cartilage (3).

The lingual mucosa (2) with its stratified squamous epithelium (1) covers the
apex of the epiglottis and about half of the laryngeal mucosa (7) (posterior

side). Toward the base of the epiglottis on the laryngeal surface (7), the lining
stratified squamous epithelium (1) changes to pseudostratified ciliated
columnar epithelium (8). Located below the epithelium in the lamina propria
(6) on the laryngeal side (7) of the epiglottis are tubuloacinar seromucous

glands (6).

In addition to the tongue, taste buds (5) and solitary lymphatic nodules may
be observed in the lingual epithelium (2) or laryngeal epithelium (7).

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