Yawns are more contagious among people with closer relationships.
163
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
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
Our eyes are always the same size from birth, but our nose and ears never stop growing.
266
It takes about 20 seconds for a red blood cell to circle the whole body.
102
When you take a step, you are using up to 200 muscles.
886
If you are cold you are more likely to be hungry because you use energy to keep warm.
143