In 30 minutes, the average body gives off enough heat (combined) to bring a half gallon of water to boil.
198
Yawns are more contagious among people with closer relationships.
163
Enamel is hardest substance in the human body.
61
The average sperm cell swims at 8 inches per hour.
4
Cats have a weak sense of taste. They have only 473 tastebuds, humans have 9,000.
307
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The human eye blinks an average of 4,200,000 times a year.
233