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Did you know?

Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.

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The U.S. Pharmacopeia Medication Errors Reporting Program states that approximately 50% of all medication errors involve insulin.

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The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.

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About 600,000 particles of skin are shed every hour by each human. If you live to age 70 years, you have shed 105 pounds of dead skin.

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Acute bronchitis is an inflammation of the breathing tubes (bronchi), which causes increased mucus production and other changes. It is usually caused by bacteria or viruses, can be serious in people who have pulmonary or cardiac diseases, and can lead to pneumonia.

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Video: Embryonic development - Weeks 5 to 8

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