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There are more sensory neurons in the tongue than in any other part of the body.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
The B-complex vitamins and vitamin C are not stored in the body and must be replaced each day.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
In most cases, kidneys can recover from almost complete loss of function, such as in acute kidney (renal) failure.
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