|
Author Question: Which of these is not one of the categories used by the authors of the text to classify interest ... (Read 30 times) |
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
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 first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
Asthma attacks and symptoms usually get started by specific triggers (such as viruses, allergies, gases, and air particles). You should talk to your doctor about these triggers and find ways to avoid or get rid of them.
Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.