Kidneys usually come in pairs. In a healthy body, one kidney is enough to get the job done. This is why people can donate a kidney and still live normal lives. Click on the animation play button to learn more about how the kidneys perform their tasks.
Animation Voice Over:
You have two kidneys, found in the middle of the lower back above the waist, one on each side of the spine. Each kidney is about the size of your fist and weighs about a quarter of a pound. Blood travels to your kidneys through blood vessels called the renal arteries, and away from the kidneys through the renal veins. Urine is made in the kidneys and flows through tubes called the ureters, to the bladder, where it is stored. When you urinate, the urine empties from the bladder through the urethra. The entire system is called the urinary tract.
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