You can hear the blood flowing through your ears if you find a quiet place and cover them tightly.
19
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
In one day, adult lungs move about 10,000 litres of air.
11
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515
The average sperm cell swims at 8 inches per hour.
76
The human brain uses approximately as much energy as a 10 watt light bulb.
120
All humans have the ability to see ultraviolet light, but it is passively filtered out by the eye's lens. People who undergo surgery to remove the lens can detect ultraviolet light.
22
The average person's skin weighs twice as much as their brain.
131