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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.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
The familiar sounds of your heart are made by the heart's valves as they open and close.
According to the American College of Allergy, Asthma & Immunology, more than 50 million Americans have some kind of food allergy. Food allergies affect between 4 and 6% of children, and 4% of adults, according to the CDC. The most common food allergies include shellfish, peanuts, walnuts, fish, eggs, milk, and soy.
There are approximately 3 million unintended pregnancies in the United States each year.