It takes about 20 seconds for a red blood cell to circle the whole body.
102
Yawns are more contagious among people with closer relationships.
163
Your body is creating and killing about 2.4 million red blood cells per second.
17
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Enamel is hardest substance in the human body.
61
Poor eyesight (myopia) is associated with higher IQ.
232
The average person's skin weighs twice as much as their brain.
131
The human brain doesn't stop developing until about 25 years old.
102