Endergonic

Endergonic (from the suffix endo-, derived for the Greek word ἔνδον endon, "within" and the English suffix -ergonic, derived from the Greek word ἔργον ergon, "work") means "absorbing energy in the form of work." Endergonic reactions are not spontaneous. By thermodynamic standards, work, a form of energy, is defined as moving from the surroundings (the external region) to the system (the internal region). Thus, an endergonic process, as contrasted with an exergonic process, is one wherein the system absorbs energy from the surroundings. As a result, during an endergonic process, energy is put into the system. If the transformation occurs at constant pressure and temperature, ∆G > 0. An endergonic reaction is a chemical reaction that absorbs energy in the form of work. A good example of an endergonic reaction is photosynthesis. Also, in metabolism, an endergonic reaction is anabolic, meaning, the storage of energy. In metabolism, catabolic and anabolic are coupled by ATP.