Yawns are more contagious among people with closer relationships.
163
When you take a step, you are using up to 200 muscles.
886
The average sperm cell swims at 8 inches per hour.
76
The human brain is very soft, having a consistency similar to soft gelatin or firm tofu.
13
Your thumb is about the same size as your nose.
124
Quick naps not only improve your alertness, but they also help in decision making, creativity and sensory perception.
149
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118