The Bladder
The bladder is a hollow, balloon-like organ in the lower abdomen that stores and collects urine. Urine is composed of water and waste products that are not needed by the body. It is produced by both kidneys and passed into the bladder through two tubes called ureters. A layer of muscle surrounds the inner lining of the bladder. When the bladder becomes full, nerve signals are sent to the brain and the muscles in the bladder wall tighten to squeeze the bladder and push the urine out. Urine leaves the bladder through a tube called the urethra.
