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.
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Your heart pumps about 2,000 gallons of blood each day!
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Your heart will pump about 212 million liters in its lifetime.
26
Holding hands with someone you love can alleviate physical pain as well as stress and fear.
26
In 1996, research found that having excessive body hair is linked to higher intelligence.
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Your stomach produces a new layer of mucus every two weeks so that it doesn't digest itself.
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Your body is creating and killing about 2.4 million red blood cells per second.
17
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
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