Glycolysis is the first and foremost step of cellular respiration which is available in almost all living beings. Through the Glycolysis pathway, the glucose gets broken down into pyruvic acid, which produces the energy required for sustaining life. The two pyruvate molecules are produced, including water, ATP and NADH. It is common in both anaerobic and aerobic respiration. In the Glycolysis process, oxygen is not required. Today, here, we are going to read What is Glycolysis, What is the Glycolysis equation in detail along with other related topics. So, without any further ado, let’s get started!
Overview of Glycolysis
Glycolysis can be described as the series of enzymatic reactions which takes place in the cytoplasm. The other name of glycolysis is the EMP pathway or Embden Meyerhof Parnas pathway. In cellular respiration, it is the first step. Animals are plants that get the energy to perform everyday activities by breaking down carbohydrates. Further, the Sucrose, which is safely stored in the plants, is transformed into fructose and glucose.
During aerobic respiration, the Krebs cycle follows glycolysis. When the oxygen is not present, small amounts of ATPs are formed as glycolysis which is further followed by fermentation. Three German biochemists named Gustav Embden, Otto Meyerhof, and Jakub Karol Parnas came up with the metabolic pathway in the early 19th century; hence it is named as EMP pathway.
Path of Glycolysis
The following are the stages in which glycolysis takes place –
- Stage 1
In the cell cytoplasm, a phosphate group is included in the glucose by the enzyme hexokinase action. Here, the phosphate group gets transferred from the ATP to the glucose to form glucose-6-phosphate.
- Stage 2
Glucose-6-phosphate is isomerised into the fructose,6-phosphate through the enzyme phosphoglucomutase.
- Stage 3
Another ATP molecule transfers the phosphate group to the fructose 6-phosphate, which gets converted into the fructose 1,6-bisphosphate by enzyme phosphofructokinase actions.
- Stage 4
The fructose 1,6-bisphosphate is converted into the dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. Both of these are the isomers of one another.
- Stage 5
Dihydroxyacetone phosphate is converted into the glyceraldehyde 3-phosphate through the Triose-phosphate isomerase.
- Stage 6
In step 6, the following step undergoes –
One hydrogen molecule is transferred from nicotinamide adenine dinucleotide to glyceraldehyde phosphate in order to form NADH + H+
- Stage 7
Phosphate gets transferred from 1,3-bisphosphoglycerate to the ADP in order to form ATP through phosphoglycerokinase. Hence, the two phosphoglycerate molecules are achieved by the end of the reaction.
- Stage 8
The phosphoglycerate molecules have phosphate, which is relocated from the third to the second carbon for yielding two molecules of 2-phosphoglycerate.
- Stage 9
A water molecule is removed by the enzyme enolase from 2-phosphoglycerate in order to build phosphoenolpyruvate.
What is Glucose?
Glucose is essential because it gives many organisms energy and structure. Glucose molecules are broken down in glycolysis to provide energy and precursors for cellular respiration. When a cell does not require additional energy, glucose can be stored by mixing it with other monosaccharides. These lengthy chains are stored as starch by plants, which can be deconstructed and used as energy later. The polysaccharide glycogen, which can hold a lot of energy, is used by animals to store glucose chains.
What are Fructose and Galactose?
It is a sugar that does not reduce. Sucrose is formed when fructose combines with glucose. Fructose is found in fruits like cherries. Fructose is commonly generated commercially from sugar cane, sugar beets, and corn. Annually, over 240,000 tonnes of crystalline fructose are produced. In all forms, including fruits and juices, fructose is widely added to foods and beverages to improve taste and brown various dishes, such as baked products. Excessive fructose consumption has been linked to insulin resistance, obesity, and high LDL cholesterol, which can contribute to type 2 diabetes and cardiovascular disease.
Galactose is a monosaccharide that is produced by a variety of species, including mammals. Galactose is a sugar found in milk that mammals use to provide energy to their children. Lactose is formed when galactose and glucose are mixed. Lactose connections contain a lot of energy, and newborn mammals produce specific enzymes to break them apart. The enzymes that break lactose down into glucose and galactose monosaccharides are lost once a child is weaned from their mother’s milk.
Conclusion
With this, we come to the end of the topic: What is Glycolysis? Glycolysis can be described as the series of enzymatic reactions which takes place in the cytoplasm. The other name of Glycolysis is the EMP pathway or Embden Meyerhof Parnas pathway. In cellular respiration, it is the first step. Animals are plants that get the energy to perform everyday activities by breaking down carbohydrates.
There are a total of nine stages of glycolysis which we discussed in detail. At the last stage, a water molecule is removed by the enzyme enolase from 2-phosphoglycerate in order to build phosphoenolpyruvate. At last, we also discussed Fructose and Galactose in brief for better understanding.