The urinary system, often referred to as the urinary tract or renal system, acts as a filter to remove wastes from the body. It is also responsible for regulating blood pressure and volume, controlling the number of electrolytes in the body, and regulating pH levels in blood. The normal human urinary system includes two kidneys, a bladder, two ureters that each lead from a kidney to the bladder, and the urethra, a tube that is connected to the bladder and transports urine out of the body. The male and female urinary systems are similar aside from a difference in urethral length.
At A Glance
- The urinary system is comprised of two kidneys, two ureters, a urinary bladder, and a urethra.
- The kidneys are surrounded by layers of supportive connective tissue that cover the main regions of the kidneys, the renal cortex and the renal medulla.
Kidneys produce urine and play a role in the regulation of water volume, blood pressure, electrolyte concentrations, pH levels, calcium levels, and red blood cell counts.
Blood flows into the kidneys through the afferent arteriole and the glomerulus.
- The ureters move urine to the urinary bladder by peristalsis.
- When the bladder is full, sense receptors send a signal to the pons and cerebrum to contract the muscles and open the internal sphincters so urine can be released.