All living creatures, be it man or the smallest bacteria have one function in common, which is known as respiration. During respiration, two important functions are performed in living things. In the first, electrons that were generated during the catabolism are disposed off and in the second, ATP (also known as adenosine tri-phosphate) is produced. Respiration is conducted from the cell membranes through the prokaryotes, which is found inside the mitochondria.
There are two types of respiration (i) aerobic respiration and (ii) anaerobic respiration. While aerobic respiration is a process that requires oxygen, but in anaerobic respiration, oxygen is not required. Therefore aerobic and anaerobic respiration differs in terms of the amount of energy that is produced.
In aerobic respiration, oxygen is always required. During the process of aerobic respiration, the molecules of food are broken down to obtain energy. Oxygen is present at the end point of the electron acceptor. The molecules of fuel that are generally used by the cells of the body during the process of the respiration are composed of glucose, fatty acids and amino acids. In other words, when there is respiration through the aerobic process, Glucose together with Oxygen produces Energy, Carbon Dioxide and Water.
A lot of energy is produced during aerobic respiration, which may be as high as 38 ATP molecules for every glucose molecule. This means that during aerobic respiration only one molecule of glucose will produce about thirty-eight energy units.
In plain language, anaerobic means where there is no air and thus anaerobic respiration is a term used for the respiration that occurs without the use of oxygen. In this process, the molecules carry oxidation, when oxygen is absent. This results in the production if energy or ATP. This type of respiration is also equivalent to fermentation when energy production path (Glycolytic pathway) is functioning in one cell. There are two processes of this respiration (i) alcoholic fermentation, where the Glucose gets broken down and produces Energy (ATP), Ethanol and Carbon Dioxide as well as (ii) Lactate fermentation where Glucose breaks itself into Energy and Lactic Acid.
Anaerobic respiration produces less energy when compared with the process of aerobic respiration. This can be best illustrated with the fact that during the anaerobic respiration only two molecules of ATP are yielded for one glucose molecule
Anaerobic respiration produces less energy in comparison to aerobic respiration. When the anaerobic respiration (alcoholic fermentation) as at one above functions, only two molecules of ATP are given out for one glucose molecule, while for lactate fermentation as at two above, 2 ATP molecules are given out for each glucose molecule used during the process. Thus, during anaerobic respiration, only one molecule of glucose is broken down to obtain only 2 ATP molecule.
Generally anaerobic respiration is always used by the primitive living organisms, which live in places where oxygen is missing, like muddy bottom of a river. In such places, the organism survives without depending to a large extent on oxygen. These habitats are known as anoxic.