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There are more sensory neurons in the tongue than in any other part of the body.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
Everyone has one nostril that is larger than the other.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
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