For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
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 average person's skin weighs twice as much as their brain.
131
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The human brain has the capacity to store everything that you experience.
4k
One human hair can support 3 ounces.
191