Metabolism Metabolism Metabolism is a general term used to refer to all of the chemical reactions which occur in a living system. In terms of oxidation-reduction principles, anabolic reactions are primarily characterized by reduction reactions, such as the dark reaction in photosynthesis where carbon dioxide is reduced to form glucose.
Catabolic reactions are primarily oxidation reactions.
Although catabolism involves many separate reactions, an example of such as process can be described by the oxidation of glucose as shown below. Note that this equation is the reverse of the photosynthetic equation. At the same time, each oxygen atom is reduced by gaining 2 electrons when it is converted to water. Catabolic reactions can be divided into many different groups of reactions called, catabolic pathways. These compounds are then utilized to provide energy for driving the cellular machinery.