Question: why is blood red but your vins r blue

Julie Greensmith answered on 22 Jun 2011:

Blood is never blue. Ever. Sometimes it is more red or brown depending on how much oxygen is in the blood cells. The reason it looks bluish is the colour combinations between the pigments in blood, the blood vessels and the pigments in lots of layers of skin. Veins are more commonly purple to look at on the surface of the skin. People used to think that veins were blue and arteries are red but this is not true either.