Ever wonder why bruises turn black and blue?

A bruise is caused by a blow that is hard enough to break the tiny blood vessels under the skin. This causes blood to seep into surrounding areas where it can no longer get the oxygen that was supplied through the blood vessels. Since it is oxygen that gives blood its red color, this oxygen-deprived blood now turns blue. Any part of this blue blood that is seen through pink or reddened skin will appear black, thus giving bruises their black and blue appearance.

A bruise is caused by a blow that is hard…