Question

Write a short note on glycolysis.

Answer 1

Hint: Glycolysis is an anaerobic process that takes place in the cell cytoplasm. Glycolysis is the stage where 1 glucose molecule is broken down into 2 molecules of pyruvate along with the release of energy.

Complete answer
The glycolysis cycle begins when the glucose molecule is broken down due to certain conditions and results in the formation of the two molecules of pyruvic acid. In each glycolysis cycle, one ATP molecule is produced, and therefore 2 glycolysis cycles for 1 molecule of glucose. Thus, from 1 molecule of glucose 2 ATP molecules are produced. This cycle takes place outside the mitochondria. A total of 4 ATP molecules are produced in this whole cycle, out of which 2 ATP molecules are utilized in the process itself while the remaining 2 ATP molecules will be the net gain of the glycolysis cycle. Thus this process is called an exothermic reaction.

Additional information
Gustav Embden, Otto Meyerhoff, and Jakub Karol Parnas in 1918 were the first to describe the process of glycolysis which is also referred to as the EMP pathway. It is the most common type of glycolysis.
The term Glycolysis is taken from the two words, “glycan” meaning sugar and “lysis” meaning splitting so the term simply means splitting up of sugar. The pathway of glycolysis is divided into two different phases which are listed below:
The Preparatory (or Investment) Phase. In this phase, ATP is consumed.
The Pay-Off Phase - In this phase, the production of ATP occurs.

Note:
The process of Glycolysis involves catalyzed reactions that involve ten enzymes. As the breakdown in the case of the glucose molecule occurs similarly the other monosaccharides as fructose and galactose will also break down and result in the formation of their intermediates. Glycolysis is a metabolic pathway which is found in almost all the living organisms. It is found to be dependent upon the presence of oxygen and has an evolutionary history.