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Did you know?

Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.

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Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.

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In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.

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Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%

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Immunoglobulin injections may give short-term protection against, or reduce severity of certain diseases. They help people who have an inherited problem making their own antibodies, or those who are having certain types of cancer treatments.

McCourt and colleagues engineer drought tolerance into crops. McCourt and colleagues engineer drought tolerance into crops.
In the summer of 1793, a yellow fever epidemic struck Philadelphia, killing nearly 4,000. Tens of th In the summer of 1793, a yellow fever epidemic struck Philadelphia, killing nearly 4,000. Tens of th
A passenger train crosses Stony Creek Bridge in the Rocky Mountains in 1878. Railroads were importan A passenger train crosses Stony Creek Bridge in the Rocky Mountains in 1878. Railroads were importan
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Video: Factors that affect conduction rates (myelination, axon diameter & temperature)

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