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Author Question: Which of the following is not a variation that occurs in the structure and inner workings of the ... (Read 42 times) |
The familiar sounds of your heart are made by the heart's valves as they open and close.
The senior population grows every year. Seniors older than 65 years of age now comprise more than 13% of the total population. However, women outlive men. In the 85-and-over age group, there are only 45 men to every 100 women.
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
Asthma cases in Americans are about 75% higher today than they were in 1980.
Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.