Water 70% of the human heart is water, that's about the same amount covering the surface of the earth. View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize View fullsize