Yawns are more contagious among people with closer relationships.
163
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Every year your body replaces 98% of your atoms.
119
The average sperm cell swims at 8 inches per hour.
76
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Poor eyesight (myopia) is associated with higher IQ.
232
When you take a step, you are using up to 200 muscles.
886