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Vaccines prevent between 2.5 and 4 million deaths every year.
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
The average office desk has 400 times more bacteria on it than a toilet.
Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.
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