It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
The average sperm cell swims at 8 inches per hour.
76
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Enamel is hardest substance in the human body.
61
An average heart beats 100,000 times a day, pumping some 2,000 gallons of blood through its chambers. Over a 70-year life span, that adds up to more than 2.5 billion heartbeats.
73
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
Yawns are more contagious among people with closer relationships.
163