Photosynthesis is the process by which b) glucose is synthesized. In the reactions of photosynthesis, carbon dioxide and water are the reactants. They are converted into glucose (sugar) and oxygen gas, and the reaction is powered by the sun's energy. Chlorophyll is the green pigment that absorbs light energy from the sun, utilizing this energy to drive the reactions in photosynthesis. The glucose that is created serves as food for the plants and for nearly every other living thing. Glucose stores the sun's energy in its chemical bonds and this energy can be accessed later when the glucose is broken apart through cellular respiration.