For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Our Right Lungs takes more air than our left lung.
194
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
The average sperm cell swims at 8 inches per hour.
76