General Education Drills Practice Test 2026 – Your Comprehensive All-in-One Guide to Exam Success!

Light energy provides the input needed to drive photosynthesis, enabling the formation of chemical bonds that store energy in glucose. In the balanced equation, the energy from light is treated as a reactant because its energy is absorbed and consumed to power the steps that convert carbon dioxide and water into glucose and oxygen. Without this energy input, the reaction wouldn’t proceed. It isn’t a product, since no energy is produced by the reaction, and it isn’t a catalyst, because the energy from light is used up in making new chemical bonds rather than simply speeding up the reaction while remaining unchanged.