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Health | Human Body | Kidney & Urinary Tract

The role of the urinary system is to cleanse the blood. Arterial blood is filtered through the kidneys and returned to the circulation. Learn more about how the urinary system monitors the concentration of salts and other necessary nutrients.

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How Your Kidneys Work

The kidneys spend 24 hours a day, seven days a week filtering gallons and gallons of blood. But that's not all these little bean-shaped organs accomplish in a day.


Is urine really sterile?

 Is urine really sterile?

'Pee on it' has long been the advice for a jellyfish sting or even a regular cut if nothing else is available. But is urine really sterile? Find out. See more »

Can you hold your pee so long your bladder ruptures?

 Can you hold your pee so long your bladder ruptures?

Could holding your pee for a long time have serious consequences? Find out if holding your pee too long can cause your bladder to rupture. See more »

How Your Kidneys Work

 How Your Kidneys Work

The kidneys perform several important tasks. Learn about kidney processes and how the kidneys maintain water volume and balance and regulate blood composition. See more »