Anaerobic glycolysis
Encyclopedia
Anaerobic glycolysis is the transformation of glucose
to pyruvate when limited amounts of oxygen
(O2) are available. Anaerobic glycolysis is only an effective means of energy production during short, intense exercise, providing energy for a period ranging from 10 seconds to 2 minutes. The anaerobic glycolysis (lactic acid) system is dominant from about 10–30 seconds during a maximal effort. It replenishes very quickly over this period and produces 2 ATP
molecules per glucose molecule, or about 5% of glucose's energy potential (38 ATP molecules). The speed at which ATP is produced is about 100 times that of oxidative phosphorylation
. The pH in the cytoplasm
quickly drops when hydrogen ions accumulate in the muscle, eventually inhibiting enzymes involved in glycolosis.
The burning sensation in muscles during hard exercise can be attributed to the production of hydrogen ions during a shift to anaerobic glycolysis as oxygen is converted to carbon dioxide
by aerobic glycolysis faster than the body can replenish it. These hydrogen ions form a part of lactic acid along with lactate. The body falls back on this less efficient but faster method of producing ATP under low oxygen conditions. This is thought to have been the primary means of energy production in earlier organisms before oxygen was at high concentration in the atmosphere and thus would represent a more ancient form of energy production in cells.
The liver
later gets rid of this excess lactate by transforming it back into an important glycolytic intermediate called pyruvate. Aerobic glycolysis is a method employed by muscle cells for the production of lower-intensity energy over a longer period of time.
The process of converting the excess lactate back into pyruvate is known as the Cori cycle
, and occurs in the liver.
Many anaerobic microorganisms carry out Anaerobic Glycolysis through Fermentation
.
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
to pyruvate when limited amounts of oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
(O2) are available. Anaerobic glycolysis is only an effective means of energy production during short, intense exercise, providing energy for a period ranging from 10 seconds to 2 minutes. The anaerobic glycolysis (lactic acid) system is dominant from about 10–30 seconds during a maximal effort. It replenishes very quickly over this period and produces 2 ATP
Adenosine triphosphate
Adenosine-5'-triphosphate is a multifunctional nucleoside triphosphate used in cells as a coenzyme. It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism...
molecules per glucose molecule, or about 5% of glucose's energy potential (38 ATP molecules). The speed at which ATP is produced is about 100 times that of oxidative phosphorylation
Oxidative phosphorylation
Oxidative phosphorylation is a metabolic pathway that uses energy released by the oxidation of nutrients to produce adenosine triphosphate . Although the many forms of life on earth use a range of different nutrients, almost all aerobic organisms carry out oxidative phosphorylation to produce ATP,...
. The pH in the cytoplasm
Cytoplasm
The cytoplasm is a small gel-like substance residing between the cell membrane holding all the cell's internal sub-structures , except for the nucleus. All the contents of the cells of prokaryote organisms are contained within the cytoplasm...
quickly drops when hydrogen ions accumulate in the muscle, eventually inhibiting enzymes involved in glycolosis.
The burning sensation in muscles during hard exercise can be attributed to the production of hydrogen ions during a shift to anaerobic glycolysis as oxygen is converted to carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
by aerobic glycolysis faster than the body can replenish it. These hydrogen ions form a part of lactic acid along with lactate. The body falls back on this less efficient but faster method of producing ATP under low oxygen conditions. This is thought to have been the primary means of energy production in earlier organisms before oxygen was at high concentration in the atmosphere and thus would represent a more ancient form of energy production in cells.
The liver
Liver
The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
later gets rid of this excess lactate by transforming it back into an important glycolytic intermediate called pyruvate. Aerobic glycolysis is a method employed by muscle cells for the production of lower-intensity energy over a longer period of time.
The process of converting the excess lactate back into pyruvate is known as the Cori cycle
Cori cycle
The Cori cycle , named after its discoverers, Carl Cori and Gerty Cori, refers to the metabolic pathway in which lactate produced by anaerobic glycolysis in the muscles moves to the liver and is converted to glucose, which then returns to the muscles and is converted back to lactate.-Cycle:Muscular...
, and occurs in the liver.
Many anaerobic microorganisms carry out Anaerobic Glycolysis through Fermentation
Fermentation (biochemistry)
Fermentation is the process of extracting energy from the oxidation of organic compounds, such as carbohydrates, using an endogenous electron acceptor, which is usually an organic compound. In contrast, respiration is where electrons are donated to an exogenous electron acceptor, such as oxygen,...
.