Yawns are more contagious among people with closer relationships.
163
Enamel is hardest substance in the human body.
61
Our Right Lungs takes more air than our left lung.
194
The average sperm cell swims at 8 inches per hour.
76
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The human brain doesn't stop developing until about 25 years old.
102
Stress can result in more headaches as a result of the body rerouting blood flow to other parts of the body.
92
For most people, no matter how hard you pinch the skin on your elbow with your fingers it doesn't hurt.
515