Respiration is a process through which energy is released from glucose or another organic chemicals. As such, it is significant for the survival of all living organisms, whether human beings or microscopic bacteria. It serves two fundamental purposes in living beings: first is the removal of the electrons generated during catabolism and second, is generation of ATP (adenosine triphosphate). But respiration occurs in two different ways, namely, aerobic and anaerobic. Aerobic respiration is oxygen-based cellular respiration that uses oxygen to generate energies through the breakdown of carbohydrates, fats, and proteins. Anaerobic respiration, on the other hand, is cellular respiration that takes place without oxygen and begins the breakdown process using electron acceptors and instruments, but does not use oxygen. Go through the following text to know all about anaerobic respiration.
Process Of Anaerobic Respiration
Anaerobic respiration takes place through fermentation process, also known as glycolysis. Fermentation is the process through which glucose molecules are split into two molecules of pyruvic acid. As such, fermentation produces two ATP molecules, which are further used to split a glucose molecule into two three-carbon atom chains. These two chains have one-phosphate group at their ends. During the process, another phosphate group is added to the end of each three-carbon chain. Thus, these two phosphate groups on each chain are later divided between two molecules known as adenosine diphosphate (ADP). Therefore, ADP is transformed into ATP. Anaerobic respiration is a less efficient process of cellular respiration which produces only two molecules of ATP as compared to 40 ATP produced in aerobic respiration. As such, anaerobic respiration generates less energy. However, it is a faster method as opposed to aerobic respiration.
In human beings, it is the muscle tissue that respires anaerobically, generally during exercising. It is during this time that the body cannot take in the required oxygen, allowing the cells to respire. As such, during exercising, not much energy is produced and hence, muscles require more energy to breathe. Therefore, to achieve this, muscles extract energy in the absence of oxygen, thereby using anaerobic respiration and producing lactic acid. However, when a body stops exercising, an oxygen debt occurs due to the presence of large amount of lactic acid in the muscles. It is due to this reason that humans start breathing heavily and the muscles become weak and start paining immediately after exercising to overcome the oxygen debt.
During anaerobic respiration, carbohydrates are partly oxidized and hence, chemical energy is released without the presence or requirement of oxygen. Apart from carbohydrates and muscles, some yeasts and bacteria also indulge in anaerobic respiration. Fermentation of alcohol, which produces ethanol, is another example of anaerobic respiration. This implies that the main purpose of anaerobic respiration is producing ATP (adenosine triphosphate) which is essential for a cell to produce energy. Anaerobic respiration is a prehistoric process that began when even oxygen was missing from the atmosphere above earth. As such, many living organisms have adapted to such kinds of environments and habitats that are otherwise not suitable for several other living organisms.
Types of Anaerobic Respiration
Nitrate reduction reduces nitrate (NO3-) into nitrite (NO2-), thereby utilizing hydrogen and producing water during the process. In some cases, several microorganisms are capable of reducing nitrite even further all the way to nitrogen gas. However, during this process, the bacteria have to be very careful as some intermediate products can be toxic.
Sulfate reduction is often noticed in organisms that survive in environments with very small amounts of oxygen. This process works by reducing sulfate (SO4-2) into sulfide (S-2).
Energy can be produced through several ways, one of them being by reducing carbonate. Most organisms start producing energy with carbonate (CO3) by reducing it to methane (CH4) or acetic acid (CH3COOH).
Hope this information must have given you know-how about anaerobic respiration. Similar to aerobic respiration, anaerobic respiration is also essential for the survival of certain living organisms.