Metabolism
Metabolism is the system of chemical activities by which the living thing gets power (energy) from other things such as food. Your metabolism can work more or less. This depends for example on how often you eat. If you are hungry your metabolism slows down dramatically. Your metabolism uses energy to fuel all organs involved in digestion and respiration and so on. The amount of energy used to carry out ase life processes is called your BMR-rate or your "basal metabolic rate".
