Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The human body contains over a billion miles of DNA.
147
One human hair can support 3 ounces.
191
The average sperm cell swims at 8 inches per hour.
76
Chewing gum boosts your brain power.
285
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