Respiration is one of the important chemical processes, which is carried out by all living organisms including plants and animals in order to release the energy required for life processes.
The process of respiration occurs both during the presence or in the absence of oxygen.
When a breakdown of the respiratory substrate takes place in the presence of oxygen is called aerobic respiration, if glucose is the respiratory substrate then 36-38 ATP molecules are formed after a complete breakdown of one glucose molecule.
When the breakdown of the respiratory substrate takes place in absence of oxygen is called anaerobic respiration (Fermentation), only 2 molecules of ATP are formed from glucose after the breakdown.
Thus, aerobic respiration produces far more ATPs than anaerobic respiration.