Why do some people blush/turn red when they're embarassed?

I've always wondered how some people are able to turn red just because they're embarassed or angry. And how come some people can do it and others can't?Why do some people blush/turn red when they're embarassed?
it's simple. It has to do with a biological reaction. More blood is pump through the veins. the melanin levels of the individual effect the degree which the 'blushing' is noticed, which is why dark-skinned africans don't appear to blush even though the blood flow is much the same. Anger causes the same reaction as does anything that causes exertion or extreme emotion.Why do some people blush/turn red when they're embarassed?
Some people blush when they're embarrassed and others have crazy looks on their face when their embarrased. I'm not sure why, likely genetics.
Idk..lol but I am one of those people that their face turns red when i laugh a lot %26amp; when i am embarrassed.I am also one of those people that when they get mad or really really embarrassed they can feel the heat come off their face. lol its funny.. but its kind of embarassing to turn red from being embarassed you know? lol