The average sperm cell swims at 8 inches per hour.
76
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
An Indian man known as "Snake Manu" can put small snakes, including deadly cobras, into his mouth and pass them out through his nose.
59
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190