Color
(Venous blood is always blue through the opaque skin).
The appearance of veins as dark blue is a wavelength phenomenon, having to do with the reflection of blue light away from the outside of venous tissue if the vein is at 0.02 inches deep or more. Deoxygenated blood is darker than oxygenated blood due to the difference in color between deoxyhemoglobin and oxyhemoglobin.
Read more about this topic: Venous Blood
Famous quotes containing the word color:
“... ideals, standards, aspirations,—those are chameleon words, and take color from their speakers,—often false tints. A scholarly man of my acquaintance once told me that he traveled a thousand miles into the desert to get away from the word uplift, and it was the first word he heard after he reached his destination.”
—Carolyn Wells (1862–1942)