It takes about 20 seconds for a red blood cell to circle the whole body.
102
The average sperm cell swims at 8 inches per hour.
76
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Your thumb is about the same size as your nose.
124
One human hair can support 3 ounces.
191
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266