Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
The human brain doesn't stop developing until about 25 years old.
102
There are times when you're walking that the pressure on your feet exceeds your body weight, and when you're running, it can be three or four times your weight.
62
Yawns are more contagious among people with closer relationships.
163
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
When you get goosebumps and your hair stands, the hair helps to trap air, making you feel warmer by keeping in your body heat.
46