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If you could remove all of your skin, it would weigh up to 5 pounds.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
In 1864, the first barbiturate (barbituric acid) was synthesized.
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