The Urinary System
The urinary system is concerned with the formation and elimination of urine. In an adult, more than 2,500 pints of blood passes through the kidneys each day. Blood enters via the renal arteries and is filtered to remove most of the waste products of metabolism. Seven pints of filtrate are produced every hour. Purified blood returns to the body circulation via the renal veins. The filtering process is carried out by more than two million tiny kidney units, or nephrons, which produ
Anatomy of a Kidney
This cross section of a kidney, almost three times life-size, shows its blood supply and one of the filter tubules, a nephron, highly magnified. The nephron is a highly specialized coiled tubule measuring up to one inch in length. There are more than one million nephrons in each kidney. They function as the kidney's filter units. The kidneys filter unwanted materials from the blood and regulate the levels of water and chemicals in the body. As blood flows through a glomerular tu
Tour of Dissected Cat Nephron