It takes about 20 seconds for a red blood cell to circle the whole body.
102
Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Yawns are more contagious among people with closer relationships.
163
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
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
Your heart will pump about 212 million liters in its lifetime.
26