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Author Question: In participant observation, researchers interact with the people they are studying. Indicate ... (Read 67 times) |
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
According to the CDC, approximately 31.7% of the U.S. population has high low-density lipoprotein (LDL) or "bad cholesterol" levels.
In 1886, William Bates reported on the discovery of a substance produced by the adrenal gland that turned out to be epinephrine (adrenaline). In 1904, this drug was first artificially synthesized by Friedrich Stolz.
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.
The Centers for Disease Control and Prevention has released reports detailing the deaths of infants (younger than 1 year of age) who died after being given cold and cough medications. This underscores the importance of educating parents that children younger than 2 years of age should never be given over-the-counter cold and cough medications without consulting their physicians.