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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
If you could remove all of your skin, it would weigh up to 5 pounds.
Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.
The familiar sounds of your heart are made by the heart's valves as they open and close.
The average adult has about 21 square feet of skin.
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