All humans have the ability to see ultraviolet light, but it is passively filtered out by the eye's lens. People who undergo surgery to remove the lens can detect ultraviolet light.
22
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
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An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
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There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
Within three days of death, the enzymes that once digested your food begin to eat you.
22
Women have about four times as many foot problems as men; lifelong patterns of wearing high heels often are the culprit.
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For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
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