Why do the veins of human look green outside of the body?
Answers
Answer:
Explanation:
the blue or green appearance is actually caused by the light's ability to penetrate your skin and then be reflected back to your eye. The fact that these veins become more visible during your period is most likely due to the fact that your breasts are swelling. ... We all have veins that run near the surface there
hey mate...
here is your answer...
Because you are not seeing the veins, but the blood inside them!
The superficial veins have very thin walls, and when full of blood, you can see the venous blood colour (if you are caucasian!).
You should be asking: well, but blood is red! Well, venous blood is blueish, because it does not have a large concentration of oxygen, but has high concentrations of carbon dioxide. These molecules are transported by hemoglobin, the substance that gives blood its colour. The point is that oxyhemoglobin (hemoglobin + oxygen) is red and carboxyhemoglobin (hemoglobin + carbon dioxide) is dark blue (or greenish, it depends on the observer).
You can't see the arterial blood in the same way because the arterial walls are thicker and the arteriae are locates almost always deeper than the veins.
hope it helps...