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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
The average adult has about 21 square feet of skin.
The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
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