|
|
Did you know?
Thyroid conditions may make getting pregnant impossible.
Did you know?
Your heart beats over 36 million times a year.
Did you know?
Before a vaccine is licensed in the USA, the Food and Drug Administration (FDA) reviews it for safety and effectiveness. The CDC then reviews all studies again, as well as the American Academy of Pediatrics and the American Academy of Family Physicians. Every lot of vaccine is tested before administration to the public, and the FDA regularly inspects vaccine manufacturers' facilities.
Did you know?
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Did you know?
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.