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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.
About 60% of newborn infants in the United States are jaundiced; that is, they look yellow. Kernicterus is a form of brain damage caused by excessive jaundice. When babies begin to be affected by excessive jaundice and begin to have brain damage, they become excessively lethargic.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.