PATHOLOGY

Detailed explanation-1: -Urethra. This tube allows urine to pass outside the body. The brain signals the bladder muscles to tighten, which squeezes urine out of the bladder. At the same time, the brain signals the sphincter muscles to relax to let urine exit the bladder through the urethra.

Detailed explanation-2: -The opening to the outside is the external urethral orifice. The mucosal lining of the urethra is transitional epithelium. The wall also contains smooth muscle fibers and is supported by connective tissue. The internal urethral sphincter surrounds the beginning of the urethra, where it leaves the urinary bladder.