Body & HealthFact

Your blood is never blue, not even in your veins.

Deoxygenated blood is dark red, not blue. Veins look bluish under the skin because of how skin scatters light and how your visual system processes the contrast – not because of the blood's colour. In textbooks veins are drawn blue purely to tell them apart.

Useful: A colour in a diagram is a convention, not a measurement.

Source: en.wikipedia.org

BlutMythos

Difficulty:

Question on this card

What colour is deoxygenated blood inside the body?

Blue
Dark red
Purple
Colourless

Show the answer

Correct: Dark red

It is dark red; the blue impression comes from light scattering in the skin.

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