Cellular respiration is the process through which our cells get the energy to perform their functions. Since all living things are made of cells, and all cells need energy to perform life's functions, cellular respiration is necessary for all living things. There are two types of cellular respiration: aerobic and anaerobic.
During cellular respiration, food molecules are broken down from sugar molecules to energy molecules known as ATP. ATP is also considered to be the 'energy currency' of cells. ATP stores energy in a strong bond, and cells can harness this energy by breaking that bond, thereby removing a phosphate group and resulting in ADP, which can then be reconverted to ATP. At the end of anaerobic respiration, there are only two molecules of ATP produced. During aerobic cellular respiration, there are a maximum of 38 molecules of ATP formed.
The process of aerobic cellular respiration takes place mostly inside of the mitochondria, an organelle that is known as the powerhouse of the cell.
Cellular respiration is a multiple step process that breaks down food into usable cellular energy.
There are three main stages to get from food molecules to ATP: Glycolysis, the Citric acid cycle(Krebs's cycle/TCA cycle), and the Electron transport chain.