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

A five step cycle in liver cells packages ammonia into a safer molecule for excretion. The figure is taken from NIDDK, 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 liver turns nitrogen waste into urea

A five step cycle in liver cells packages ammonia into a safer molecule for excretion Breaking down amino acids releases ammonia, which is toxic at low concentrations. Liver cells run the urea cycle, combining ammonia with carbon dioxide and aspartate to make urea. Urea travels in blood to the kidneys, which filter it into 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

NIDDK

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The liver performs over five hundred essential body functionsFiltering blood detoxifying chemicals and synthesising vital proteins A liver protein keeps fluid inside blood vesselsAlbumin is the most abundant plasma protein and holds water in the circulation Broken haemoglobin becomes the pigment bilirubinRed cell haem is recycled into a yellow-green compound that leaves the body in bile The human liver can regenerate from a quarter of its original sizeFunctional liver tissue can regrow fully following surgical removal or injury The liver stores excess blood glucose as glycogen for energyHormones signal the liver to release stored sugars during fasting or exercise The body recycles most bile acids every dayAbout ninety five percent of bile acids are reabsorbed in the final part of the small intestine

Tags: liver, urea, metabolism

The liver turns nitrogen waste into urea: the short answers

Where does this come from, and can I check it?: A five step cycle in liver cells packages ammonia into a safer molecule for excretion. The figure is taken from NIDDK, 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.