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There are 60,000 miles of blood vessels in every adult human.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
Many of the drugs used by neuroscientists are derived from toxic plants and venomous animals (such as snakes, spiders, snails, and puffer fish).
Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
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