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Author Question: Which of the following statements is correct? (Read 10 times) |
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
The familiar sounds of your heart are made by the heart's valves as they open and close.
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.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
The highest suicide rate in the United States is among people ages 65 years and older. Almost 15% of people in this age group commit suicide every year.