Your kidneys act as a filtration system, processing blood to produce waste and excess fluid, which ...
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Your kidneys act as a filtration system, processing blood to produce waste and excess fluid, which are eliminated as urine. About 20% of the blood your heart pumps each minute enters the kidneys through the renal arteries. Filtering blood plasma and formation of urine takes place in structures called nephrons. The filtering process begins when the blood flows through a collection of tiny blood vessels called a glomerulus, which is within a capsule where filtered wastes collect. Waste and excess fluid pass into tiny tubes called tubules. Valuable proteins and chemicals are recycled. In the tubules, electrolytes such as sodium and potassium and water that your body needs are moved from the filter back into blood vessels through a process called resorption. After resorption, the final waste material and excess fluid collect as urine, which flows down the ureters from the kidneys to the bladder. Urine exits the bladder and your body via the urethra.