Have you ever crashed into another person when running around on the playground and so got a nasty bump? And if it’s really bad then the swelling is accompanied with hues of purple, green, and yellow surrounding the injured area. Let’s find out why all this happens.
Right under the top layer of your skin is a network of very fine tubes that carry blood known as capillaries. When you bump into something these capillaries burst and release the blood that is flowing through them into the surrounding tissue. Even though the skin does not break, blood is released into the tissue and will coagulate. Bumps normally occur when the injury is near a part of the body that is close to the bone, like on your head, shin, or forearm.
Bruising occurs due to the same reason as bumps but the different colours appear because of the blood that spills out of the capillaries into the tissue. As haemoglobin breaks down it changes colour from purple to green, then yellow and finally golden brown. Since this is not actually life-threatening, the body will automatically clean up the bruised area and your skin will be looking as good as new in a week or so.
Can you find out why you get a black eye when you break your nose?
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