The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Staying awake for 17 hours is the same for your body as drinking 2 glasses of wine.
193
Chewing gum boosts your brain power.
285
The average sperm cell swims at 8 inches per hour.
76
Enamel is hardest substance in the human body.
61
Poor eyesight (myopia) is associated with higher IQ.
232
Every year your body replaces 98% of your atoms.
119