The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
When you take a step, you are using up to 200 muscles.
886
Yawns are more contagious among people with closer relationships.
163
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
The average sperm cell swims at 8 inches per hour.
76
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217