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Thin vascular walls enable rapid diffusion of oxygen and metabolic nutrients. The figure is taken from Encyclopaedia Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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Yes. It sits on the Human Body shelf, one of 1,090 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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Capillary walls are only one single cell layer thick

Thin vascular walls enable rapid diffusion of oxygen and metabolic nutrients

Capillaries are the smallest blood vessels, with diameters so narrow that red blood cells pass through in single file. Their walls consist of a single layer of endothelial cells, allowing gas, glucose, and waste products to diffuse easily between blood and surrounding tissues.

Where this comes from

Encyclopaedia Britannica

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The body produces millions of red blood cells every secondRed blood cells circulate for about 120 days before being recycled An average adult body contains about five litres of bloodBlood accounts for roughly seven to eight percent of total adult body weight The human heart beats over one hundred thousand times dailyPumping continuously the heart propels thousands of litres of blood every day Blood plasma is composed of over ninety percent waterThe liquid portion of blood transports proteins glucose hormones and electrolytes The spleen recycles old red blood cells and stores plateletsFist-sized abdominal organ monitors blood quality and mounts immune responses Human kidneys filter roughly one hundred eighty litres of blood dailyPaired abdominal organs cleanse blood plasma and regulate fluid balance

Tags: blood, capillaries, circulation

Capillary walls are only one single cell layer thick: the short answers

Where does this come from, and can I check it?: Thin vascular walls enable rapid diffusion of oxygen and metabolic nutrients. The figure is taken from Encyclopaedia Britannica, 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 1,090 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.