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The familiar sounds of your heart are made by the heart's valves as they open and close.
Excessive alcohol use costs the country approximately $235 billion every year.
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.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
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