Catabolic reactions are a type of metabolic reaction that take place within a cell. Larger molecules are separated to form smaller molecules, as in the case of respiration where glucose is broken down to form carbon dioxide and water. Often they are hydrolysis reactions in which water molecules are used to break bonds. The breaking of these bonds produces energy, meaning that during the reaction, energy is given out and this is known as being exergonic. Catabolism is the opposite of anabolism which involves the synthesis of large molecules from smaller molecules and is endergonic as energy is used out. Both anabolic and catabolic reactions often involve the use of a catalyst in the form of an enzyme, for example Rubisco in photosynthesis.
- ↑ Royal Society of Chemistry. (November 2004) Chemistry for Biologists. Available at: http://www.rsc.org/Education/Teachers/Resources/cfb/metabolism.htm (Accessed:16/11/2015)