∞ generated and posted on 2022.01.30 ∞

Chemical reactions associated with organisms that break substances down to yield readily usable forms of energy.

Catabolism is that aspect of metabolism consisting of the breaking down of chemicals to harvest their associated chemical energy.

Generally these are reactions that either yield ATP or otherwise are involved in the production of ATP. Organic compounds such as sugars, for example, are broken down to smaller substances, ultimately carbon dioxide and water, and in the process ATP is generated. For example, see glycolysis and cellular respiration.

Note that ATP production technically is an anabolic process, that is energy-requiring and which builds things up (ADP going to ATP). Thus, catabolic pathways provide energy that drives the anabolic process of ADP phosphorylation to generate ATP.

ATP hydrolysis, in turn, is an energy yielding, catabolic process that drives much of anabolism.