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About 600,000 particles of skin are shed every hour by each human. If you live to age 70 years, you have shed 105 pounds of dead skin.
Your heart beats over 36 million times a year.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Cyanide works by making the human body unable to use oxygen.
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