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Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
There are more sensory neurons in the tongue than in any other part of the body.
Asthma occurs in one in 11 children and in one in 12 adults. African Americans and Latinos have a higher risk for developing asthma than other groups.
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