The human brain doesn't stop developing until about 25 years old.
102
Your body is creating and killing about 2.4 million red blood cells per second.
17
Yawns are more contagious among people with closer relationships.
163
It takes about 20 seconds for a red blood cell to circle the whole body.
102
If every muscle in your body could pull in one direction, you could lift nearly 25 tons.
22
Enamel is hardest substance in the human body.
61
The largest cell in the human body is the female egg and the smallest is the male sperm.
682