Page 135 - Atlas of Histology with Functional Correlations

FIGURE 4.7 ■ Pseudostratified columnar ciliated epithelium: respiratory
passages—trachea. Stain: hematoxylin and eosin. High magnification.

FUNCTIONAL CORRELATIONS 4.5 ■

Epithelium with Cilia or Stereocilia

In trachea and bronchi, pseudostratified epithelium contains both goblet

cells and ciliated cells. The motile cilia on the ciliated cells cleanse the
inspired air and transport mucus and entrapped particulate material across
the cell surfaces to the oral cavity for either swallowing or spitting out.

Simple columnar cells with motile cilia in the uterine tubes facilitate the

conduction of oocyte and sperm across their surfaces. In the efferent
ductules of the testes, ciliated cells assist in transporting sperm out of the
testis and into the ducts of the epididymis.

The lumina of the epididymis and vas deferens are lined by
pseudostratified epithelium with prominent stereocilia. These are long

nonmotile structures, and their structure is highly different from that of the
motile cilia. However, the major function of stereocilia in these organs, like
that of microvilli, is to absorb the testicular fluid in the epididymis and vas

deferens that was produced by cells in the testes. Stereocilia are also present
in the inner ear, where their function is quite different; here, they perform
sensory functions for hearing and balance or equilibrium.

FIGURE 4.8 | Transitional Epithelium: Bladder

(Unstretched or Relaxed)

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