It takes about 20 seconds for a red blood cell to circle the whole body.
102
Every year your body replaces 98% of your atoms.
119
The average sperm cell swims at 8 inches per hour.
76
The human brain doesn't stop developing until about 25 years old.
102
Your thumb is about the same size as your nose.
124
Chewing gum boosts your brain power.
285
One human hair can support 3 ounces.
191
Yawns are more contagious among people with closer relationships.
163