Ciliated Epithelium

ciliated epithelium [′sil·ē‚ād·əd ep·ə′thēl·ē·əm]

(histology)

Epithelium composed of cells bearing cilia on their free surfaces.

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Ciliated Epithelium 

in animals and man, epithelial tissue whose cells are furnished with cilia.

The movements of the cilia of each epithelial cell and of the epithelial layer as a whole are closely coordinated. Each cilium is ahead of the next in its phase of movement by a certain length of time, so that the movement of the surface of the layer as a whole appears wavelike. Ciliated epithelium lines the respiratory passages, part of the genitourinary tract, the eustachian tube, part of the tympanic cavity, the central canal of the spinal cord, and the ventricles of the brain. In some animals it is found in the integuments (for locomotion) and in the alimentary canal. The motion of the cilia moves the liquid medium and the solid particles in it. Thus, for example, the cilia help remove dust from the respiratory passages.

On the basis of electron microscopy, scientists have advanced hypotheses suggesting a link between the coordinated movement of the cilia and the breakdown of adenosine triphosphate (ATP). However, the phase of the movement (contraction or relaxation) at which the ATP is utilized has not yet been determined.

REFERENCES

Shmagina, A. P. Mertsatel’noe dvizhenie. Moscow, 1948.
Arronet, N. I. Myshechnye i kletochnye sokratitel’nye (dvigatel’nye) modeli. Leningrad, 1971.

M. E. ASPIZ