difference between aerobic and anaerobic respiration

Aerobic respiration is the process that takes place in presence of oxygen. Aerobic respiration is the metabolic process that involves break down of fuel molecules to obtain bio-chemical energy and has oxygen as the terminal electron acceptor. Fuel molecules commonly used by cells in aerobic respiration are glucose, amino acids and fatty acids.. The process of obtaining energy in aerobic respiration can be represented in the following equation: 

Glucose + Oxygen →Energy + Carbon dioxide + Water

The aerobic respiration is a high energy yielding process. During the process of aerobic respiration as many as 38 molecules of ATP are produced for every molecule of glucose that is utilized. Thus aerobic respiration process breaks down a single glucose molecule to yield 38 units of the energy storing ATP molecules. 

Anaerobic respiration 

The term anaerobic means without air and hence anaerobic respiration refers to the special type of respiration, which takes place without oxygen. Anaerobic respiration is the process of oxidation of molecules in the absence of oxygen, which results in production of energy in the form of ATP or adenosine tri-phosphate. Anaerobic respiration is synonymous with fermentation especially when the glycolytic pathway of energy production is functional in a particular cell. The process of anaerobic respiration for production of energy can occur in either of the ways represented below: 

Glucose (Broken down to) →Energy (ATP) + Ethanol + Carbon dioxide (CO2)

Glucose (Broken down to) →Energy (ATP) + Lactic acid

The process of anaerobic respiration is relatively less energy yielding as compared to the aerobic respiration process. During the alcoholic fermentation or the anaerobic respiration (represented in the first equation) two molecules of ATP (energy) are produced. for every molecule of glucose used in the reaction. Similarly for the lactate fermentation (represented in the second equation) 2 molecules of ATP are produced for every molecule of glucose used. Thus anaerobic respiration breaks down one glucose molecule to obtain two units of the energy storing ATP molecules.