Cracking your knuckles does not actually hurt your bones or cause arthritis. The sound you hear is just gas bubbles bursting.
18
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
If your DNA was stretched out it would reach to the moon 6,000 times.
256
Our Right Lungs takes more air than our left lung.
194
The adult human brain weighs about 3 pounds (1,300-1,400 g).
99
Yawns are more contagious among people with closer relationships.
163
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Your body is creating and killing about 2.4 million red blood cells per second.
17