The average sperm cell swims at 8 inches per hour.
76
The human brain doesn't stop developing until about 25 years old.
102
The average person's skin weighs twice as much as their brain.
131
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
If your DNA was stretched out it would reach to the moon 6,000 times.
256
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127