Answer: Digestion
Step-by-step explanation:
Digestion is the process by which the complex food is broken down into simpler molecules in order to derive energy from them.
The molecules then reach mitochondria where the glucose gets converted into carbon and water in the presence of oxygen and the energy is produced in the form of adenosine triphosphate.
This energy is used in the body in the various types of processes that takes place in the body of the organism.