The anaerobic organisms are totally opposite to organisms aerobic, they do not use the diatomic oxygen for growth, metabolism and differentiation, these work with different compound, giving place a subclassification if said microorganisms work with a chemical compound called pyruvate says his Metabolism is fermentative (they use fermentation), on the other hand, it is another substance other than pyruvate, if it says that it is an organism that practices anaerobic respiration.
Fermentation consists of obtaining chemical energy from a catabolic process and unfinished or incomplete oxidation of an organic compound, according to its final product it can be classified into alcoholic fermentation since it generates ethanol, lactic fermentation produces lactic acid, butyric fermentation, among others; for its part, anaerobic respirations consist of a transport chain for electrons usually similar to that of aerobic respiration but instead of the final acceptor is oxygen, in this case it would be any compound of inorganic nature.
Just as there are aerobic bacteria, anaerobic bacteria are also in existence which can live without oxygen, some of them are found inside the human body in places where there is no presence of oxygen, such as in the large intestine where they function as putrefactive bacteria. Fecal matter, according to its resistance to oxygen, can be classified as: obligate anaerobic bacteria, these cannot grow in areas where there is presence of oxygen since it is harmful and can cause its annihilation, aerotolerant bacteria will never use oxygen for their metabolic processes but can live in oxygenated environments, facultative anaerobesThey can use oxygen as the final electron acceptor, but if they are in environments where there is no oxygen, they use the fermentation pathway.
