The process by which energy stored in food is released and made available for use by living organisms is called cellular respiration.
Cellular respiration is a series of metabolic pathways that occur within the cells of organisms, and it involves the breakdown of organic molecules, such as glucose, to release energy in a form that cells can use, usually in the form of adenosine triphosphate (ATP).
The overall process of cellular respiration can be summarized in three main stages or cycles which take place in the cytoplasm and mitochondria of a cell. Cellular respiration is a fundamental process for the generation of energy in living organisms, providing the necessary ATP for various cellular activities and maintaining the energy balance within the organism.