The human brain is the most amazing and baffling organ of our body, as well as the source of many mysteries. Although the human brain makes only 2 percent of our body weight it has over 100,000 miles of blood vessels! It’s the source of every pain we feel, and yet it doesn’t have any pain sensors inside! The brain develops at the rate of 250,000 neurons per minute in early pregnancy! Check out some unbelievable facts about the most fascinating structure of the world, the human brain: