The human brain doesn't stop developing until about 25 years old.
102
Poor eyesight (myopia) is associated with higher IQ.
232
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
Enamel is hardest substance in the human body.
61
The average sperm cell swims at 8 inches per hour.
76
One human hair can support 3 ounces.
191
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197