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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Blood is approximately twice as thick as water because of the cells and other components found in it.
There are more sensory neurons in the tongue than in any other part of the body.
Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.
More than 4.4billion prescriptions were dispensed within the United States in 2016.
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