The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
The average sperm cell swims at 8 inches per hour.
76
Enamel is hardest substance in the human body.
61
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190