Enamel is hardest substance in the human body.
61
The average sperm cell swims at 8 inches per hour.
76
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46
One human hair can support 3 ounces.
191
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
Yawns are more contagious among people with closer relationships.
163
Most of us have microscopic, worm like mites named Demodex that live in our eyelashes and have claws and a mouth.
-137
The largest cell in the human body is the female egg and the smallest is the male sperm.
682