78 



THE TISSUES 



type of epithelium usually rests upon a basement membrane free from 

 papillae. The surface cells are large and frequently contain two or 

 three nuclei. Their free surfaces are flat, while their under surfaces 

 show depressions due to pressure from underlying cells. The deeper 



vrrrrTrr-rr 







^ 



f \ 





Fig. 23. — Stratified Columnar Ciliated Epithelium from the Human Trachea. A 



mucous (goblet) cell also is present. 



cells are polygonal or irregularly cuboidal. This form of epithelium 

 lines the bladder, ureter, pelvis of the kidney, and prostatic portion of 

 male urethra. 



Fig. 24. — Isolated Ciliated Cells and Goblet Cells from Dog's Trachea. X700. 



Modified Forms of Epithelium 



(a) Ciliated Epithelium. — In this form of epithelium, fine hair-like f 

 processes — cilia — extend from the surface of the cell. These cilia j 

 vary from twelve to twenty-five for each cell and may be short as in jj 



J 



I. 



