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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.
Your heart beats over 36 million times a year.
On average, the stomach produces 2 L of hydrochloric acid per day.
Blood is approximately twice as thick as water because of the cells and other components found in it.
People about to have surgery must tell their health care providers about all supplements they take.
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