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.
21
There are about 1,400 different species of bacteria in your belly button.
10
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
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
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
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
There's 100 trillion good bacteria living in your body.
17