Your thumb is about the same size as your nose.
124
The average person's skin weighs twice as much as their brain.
131
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
When you take a step, you are using up to 200 muscles.
886
The human brain doesn't stop developing until about 25 years old.
102
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18