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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.
A seasonal flu vaccine is the best way to reduce the chances you will get seasonal influenza and spread it to others.
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.
The B-complex vitamins and vitamin C are not stored in the body and must be replaced each day.
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