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.
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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.
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Alcohol acts as a diuretic. Eight ounces of water is needed to metabolize just 1 ounce of alcohol.
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More than 150,000 Americans killed by cardiovascular disease are younger than the age of 65 years.
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Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.
Examples of fermentation
Examples of animals with external gills.
Examples of deep-sea corals found in the Sable Gully, 200 km off the coast of Nova Scotia.
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Examples of Labeling Changes
Two examples of a single crossover between two nonsister chromatids