Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
197
The human brain doesn't stop developing until about 25 years old.
102
It takes about 20 seconds for a red blood cell to circle the whole body.
102
Enamel is hardest substance in the human body.
61
Your thumb is about the same size as your nose.
124
Yawns are more contagious among people with closer relationships.
163
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266