The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Enamel is hardest substance in the human body.
61
The average sperm cell swims at 8 inches per hour.
76
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Chewing gum boosts your brain power.
285
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
The human body contains over a billion miles of DNA.
147
Your thumb is about the same size as your nose.
124