It takes about 20 seconds for a red blood cell to circle the whole body.
102
It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Your thumb is about the same size as your nose.
124
The human brain uses approximately as much energy as a 10 watt light bulb.
120
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