What is photosynthesis?

Photosynthesis is the process by which green plants make food for themselves--and, indirectly, for all animals, including human beings. Without it, life as we know it on this earth would be impossible. In photosynthesis plants combine water and salts in the soil, and carbon dioxide in the air to build up organic compounds, such as sugar starch and proteins. To do this they use the energy of sunlight, which is absorbed with the help of the green dye in their in their leaves called chlorophyll.(questions and answers)