The transitional epithelium is a unique kind of epithelium exclusive to the genitourinary tract. This epithelium is actually a stratified epithelium with the ability to contract or relax as needed (but this epithelium has no contractile element). This epithelium can transition from a stratified epithelium to a simple epithelium depending on the distension of the bladder hence the name transitional. This is perfect for the bladder because this functions to accommodate the urine storage function of the bladder by increasing its compliance.
