On average, there's 100 billion neurons in the human brain.
83
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Only humans shed emotional tears.
331
Your heart will pump about 212 million liters in its lifetime.
26