Ask unlimited questions for free
There are 20 feet of blood vessels in each square inch of human skin.
The longest a person has survived after a heart transplant is 24 years.
Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
If all the neurons in the human body were lined up, they would stretch more than 600 miles.
On average, the stomach produces 2 L of hydrochloric acid per day.
For a complete list of videos, visit our video library