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Author Question: What causes computer vision syndrome? A) Glasses that are not specifically for use with computer ... (Read 60 times) |
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.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
Barbituric acid, the base material of barbiturates, was first synthesized in 1863 by Adolph von Bayer. His company later went on to synthesize aspirin for the first time, and Bayer aspirin is still a popular brand today.