Urinary System May 2014 | Page 7

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What is urine

made of?

Let's talk more about how the kidneys filter blood. When blood goes through the kidneys, water and some of the other stuff that is in blood (like protein, glucose, and other nutrients) go back into the bloodstream, while the excess stuff and waste is taken out. Urine is what is left behind. But what is it exactly?

Urine contains:

Water

Urea, a waste product that forms when proteins are broken down

Urochrome, a pigmented blood product that gives urine its yellowish color

Salts

Creatinine, a waste product that forms with the normal breakdown of muscle

By products of bile from the liver

Ammonia