Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The average sperm cell swims at 8 inches per hour.
76
Every year your body replaces 98% of your atoms.
119
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Dogs can be trained to identify the scent of lung cancer long before symptoms develop.
190
Enamel is hardest substance in the human body.
61
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217