The average sperm cell swims at 8 inches per hour.
76
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The average person's skin weighs twice as much as their brain.
131
Your heart will pump about 212 million liters in its lifetime.
26