Where does this come from, and can I check it?

Though they weigh little, the kidneys receive roughly a fifth to a quarter of cardiac output. The figure is taken from National Kidney Foundation, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a human body fact?

Yes. It sits on the Human Body shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

The kidneys take a quarter of every heartbeat

Though they weigh little, the kidneys receive roughly a fifth to a quarter of cardiac output Each kidney is supplied by a renal artery that quickly divides into a dense branching tree. That large flow lets the kidney filter plasma many times over each day rather than once. Most of the filtered water and salt is reabsorbed, so only a small fraction leaves as urine. It sits in Mondo's human body collection, one of 200 facts that each trace back to the reference below.

Where this comes from

National Kidney Foundation

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: kidney, blood-flow, heart

The kidneys take a quarter of every heartbeat: the short answers

Where does this come from, and can I check it?: Though they weigh little, the kidneys receive roughly a fifth to a quarter of cardiac output. The figure is taken from National Kidney Foundation, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a human body fact?: Yes. It sits on the Human Body shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.