When you look up at the blue sky and see white dots flying around, you’re actually seeing your own white blood cells.
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The tongue is the strongest muscle in the human body.
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Surgeons who listen to music during operations perform better than those who don't .
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Fingernails grow nearly 4 times faster than toenails.
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Although African-Americans make up only 13% of the U.S. population, they accounted for one half of the estimated new HIV/AIDS diagnoses in 2004.
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Your ribs move about 5 million times a year, every time you breathe!
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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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During a typical human life span, the human heart will beat approximately 2.5 billion times.
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