a-short-review-of-histology

Transitional Epithelium:

Transitional epithelium is a specialised stratified epithelium which is localised in the excretory parts of the urinary system
It lines:

Transitional epithelium is specialised to prevent the leakage of urine back into the body and to accommodate the regular stretching which occurs particularly in the bladder
Leakage of urine is prevented by a specialised thickening of the luminal surface of the epithelial cells which is believed to resist osmotic forces
Strong desmosomes, and tight junctions, between the epithelial cells prevent leakage between cells
The stretchability of the transitional epithelium is accomodated by an ability to reposition the layers of cells
In addition, "hinged" areas of the cell surface adj acent to the lumen allow an unfolding of "spare" cell membrane to allow coverage over a wider surface area

Micrograph of Transitional Epithelium: