Urinary Bladder and Micturition Process
Urinary Bladder The urinary bladder is a muscular sac in the pelvis, just above and behind the pubic bone. When empty, the bladder is about the size and shape of a pear. Urine is made in the kidneys and travels down two tubes called ureters to the bladder. The bladder stores urine, allowing urination to be infrequent and controlled. The bladder is lined by layers of muscle tissue that stretch to hold urine. The normal capacity of the bladder is 400-600 mL. During urination, the bladder muscles squeeze, and two sphincters (valves) open to allow urine to flow out. Urine exits the bladder into the urethra, which carries urine out of the body. Because it passes through the penis, the urethra is longer in men (8 inches) than in women (1.5 inches). What is the urinary tract? The urinary tract is the body’s drainage system for removing urine, which is made up of wastes and extra fluid. For normal urination to occur, all body parts in the urinary tract need to work together, and in the correct...