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Author Question: The alkali metal that is naturally radioactive is ________. A) rubidium B) cesium C) lithium ... (Read 42 times) |
A headache when you wake up in the morning is indicative of sinusitis. Other symptoms of sinusitis can include fever, weakness, tiredness, a cough that may be more severe at night, and a runny nose or nasal congestion.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
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.
Drying your hands with a paper towel will reduce the bacterial count on your hands by 45–60%.
Human neurons are so small that they require a microscope in order to be seen. However, some neurons can be up to 3 feet long, such as those that extend from the spinal cord to the toes.