The human brain doesn't stop developing until about 25 years old.
102
Enamel is hardest substance in the human body.
61
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Your thumb is about the same size as your nose.
124
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
It takes about 20 seconds for a red blood cell to circle the whole body.
102