Yawns are more contagious among people with closer relationships.
163
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
Poor eyesight (myopia) is associated with higher IQ.
232
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
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
The average sperm cell swims at 8 inches per hour.
76