Ask unlimited questions for free
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
The familiar sounds of your heart are made by the heart's valves as they open and close.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
Cyanide works by making the human body unable to use oxygen.
In most cases, kidneys can recover from almost complete loss of function, such as in acute kidney (renal) failure.
For a complete list of videos, visit our video library