Ask unlimited questions for free
In most cases, kidneys can recover from almost complete loss of function, such as in acute kidney (renal) failure.
Excessive alcohol use costs the country approximately $235 billion every year.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
For a complete list of videos, visit our video library