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About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
According to the National Institute of Environmental Health Sciences, lung disease is the third leading killer in the United States, responsible for one in seven deaths. It is the leading cause of death among infants under the age of one year.
During pregnancy, a woman is more likely to experience bleeding gums and nosebleeds caused by hormonal changes that increase blood flow to the mouth and nose.
Adult head lice are gray, about ? inch long, and often have a tiny dot on their backs. A female can lay between 50 and 150 eggs within the several weeks that she is alive. They feed on human blood.

![People have seen patterns in the stars since ancient times.[5] This 1690 depiction of the constellat](https://biology-forums.com/gallery/47/medium_12359_26_01_13_3_44_40.png)
