Veins Case - Why Are Veins Blue?

When someone asks the question "why are veins blue?" a likely response is that they're blue because the blood in veins is deoxygenated. While it's true that venous blood vessels carry a lower concentration of oxygen than their arterial counterparts, this isn't the reason for their blue appearance in your skin. Still, when someone invariably responds to the veins-are-blue-because-they're-deoxygenated argument with the observation that "I've never seen blue blood before" one might then hear the slightly more sophisticated-sounding but increasingly far-fetched claim that we don't ever observe blue blood because it is immediately oxidized upon contact with air.

The bright red color of arterial blood stems from a complex that's formed between hemoglobin, iron, and molecular oxygen. This complex mainly absorbs higher energy (shorter wavelength) blue and green light, leaving behind primarily just red wavelengths for our eyes to detect. However, even when blood is largely depleted of oxygen, it is never blue: it's more of a deep maroon color. And, although I have not participated in a surgery myself, those who have assure me that in surgery, veins within the body do not appear blue either. So, not only is blood not blue, but veins on their own aren't either. "Blue veins", then, are a phenomenon unique to the skin.

Blood is never blue. Blood is described as dark red (venous) or bright red (arterial). Our veins look blue because we are looking at them through our skin. The blood inside them is dark red and it doesn't reflect light very well. The blood you see when you get hurt is usually venous blood. Arterial blood comes out in spurts. It spurts every time the heart beats. However, blue is a great way to represent arteries because of the direct meaning of the color. Blue is the color of the sky and sea. It is often associated with depth and stability. It symbolizes trust, loyalty, wisdom, confidence, intelligence, faith, truth, and heaven. So, basically, blue is the color of peace and tranquility. It relates to veins because veins are what carry the blood to your heart. In simple terms, they keep you alive or in other terms, keep

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