Ask unlimited questions for free
Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
For a complete list of videos, visit our video library