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.
which complex molecules are broken down to simpler components, are classified as catabolic reactions. Taken as a group of reactions within a cell or even an organism, they can be referred to as the cell's or organism's anabolism or catabolism.
