The entire physical and chemical processes involved in the maintenance and reproduction
of life in which nutrients are broken down to generate energy and to give simpler
molecules (
catabolism) which by themselves may be used to form more complex molecules (
anabolism). In case of
heterotrophic organisms, the energy evolving from catabolic processes is made available for use by the organism.
Source:
PAC, 1992, 64, 143
(Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992))
on page 160