The human brain doesn't stop developing until about 25 years old.
102
Your thumb is about the same size as your nose.
124
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Every year your body replaces 98% of your atoms.
119
The average person's skin weighs twice as much as their brain.
131
When you take a step, you are using up to 200 muscles.
886