The average sperm cell swims at 8 inches per hour.
76
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
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
Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
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
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
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
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55