Abstract
Until today it is a widely disseminated belief that the main source of energy of eukaryotic cell is ATP. Those means that the daily intake of food is transformed into phosphate´s compounds of high energy as ATP and GTP. Supposedly this metabolic pathway is enough for 95% of our energy´s needs. However, our work about the three main causes of blindness in Mexico, taught us an astonishing fact: 99% of the energy of human retina comes from water. Furthermore, the explanation is amazing: human body has a photo-system composed by light-melanin-water (in order of abundance in the universe) with the extraordinary capacity of uses water as source of electrons.
Keywords: Cell Nucleus, Energy, Eukaryotic cell, Hydrogen, Melanin, Oxygen, Photosynthesis.