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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.
The familiar sounds of your heart are made by the heart's valves as they open and close.
The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
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