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The Sundance Sea separated the eastern part of North America from the mountain building regions inthe western part of the continent.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
The human body produces and destroys 15 million blood cells every second.
There are more nerve cells in one human brain than there are stars in the Milky Way.
Eat fiber! A diet high in fiber can help lower cholesterol levels by as much as 10%.
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