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Author Question: While a causal chain may be as long as is necessary, the authors suggest that you should have at ... (Read 33 times) |
If all the neurons in the human body were lined up, they would stretch more than 600 miles.
When Gabriel Fahrenheit invented the first mercury thermometer, he called "zero degrees" the lowest temperature he was able to attain with a mixture of ice and salt. For the upper point of his scale, he used 96°, which he measured as normal human body temperature (we know it to be 98.6° today because of more accurate thermometers).
Intradermal injections are somewhat difficult to correctly administer because the skin layers are so thin that it is easy to accidentally punch through to the deeper subcutaneous layer.
Every 10 seconds, a person in the United States goes to the emergency room complaining of head pain. About 1.2 million visits are for acute migraine attacks.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.