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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).
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
Only 12 hours after an egg cell is fertilized by a sperm cell, the egg cell starts to divide. As it continues to divide, it moves along the fallopian tube toward the uterus at about 1 inch per day.
Earwax has antimicrobial properties that reduce the viability of bacteria and fungus in the human ear.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.