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Author Question: The activity of the somatic nervous system is __________, while the activity of the autonomic ... (Read 51 times) |
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
There are more nerve cells in one human brain than there are stars in the Milky Way.
More than one-third of adult Americans are obese. Diseases that kill the largest number of people annually, such as heart disease, cancer, diabetes, stroke, and hypertension, can be attributed to diet.
Not getting enough sleep can greatly weaken the immune system. Lack of sleep makes you more likely to catch a cold, or more difficult to fight off an infection.
Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.