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Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
Drying your hands with a paper towel will reduce the bacterial count on your hands by 45–60%.
The human body produces and destroys 15 million blood cells every second.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Calcitonin is a naturally occurring hormone. In women who are at least 5 years beyond menopause, it slows bone loss and increases spinal bone density.
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