The term metabolism groups all the chemical processes and other types of reactions or transformations that take place in the cells of an organism. Metabolism is usually constituted of two sets of factors: anabolism
, which is the transformation of nutrients and living tissue; and catabolism
, which is the transformation of other elements to produce the energy required for the operation of the body. Enzymes
are proteins involved in many metabolic reactions and a deficiency
or abnormality of certain enzymes is responsible for so-called metabolic diseases
, including genetic
origin, is the most common.