Significance of Glycolysis


Process of Glycolysis

The metabolic pathway of glycolysis involves the oxidative breakdown of one glucose molecule into two pyruvates by capturing some amount of ATP and NADH. Glycolysis is the common pathway that happens in both aerobic and anaerobic respiration. 

Glucose is the only source of energy that is supplied to the brain, to function the brain properly the body must supply a sufficient amount of glucose to the brain via blood. Hence we can tell that glycolysis is the important process that takes place in the cell. 

Glycolysis: Pathway Energetics and Significance

Glycolysis occurs in both the prokaryotes and eukaryotes. Even though there are different mechanisms that happen in the body, glycolysis is the most important one as it produces the intermediate that is required for other metabolic processes. The glycolysis process occurs in the cytosol and it is a very important process in organisms that do not contain mitochondria. The end product of glycolysis is pyruvate, which acts as an intermediate of various pathways such as gluconeogenesis, fermentation, etc.

The energetics of glycolysis include, from one glucose molecule, two molecules of glyceraldehyde 3-phosphate are formed in the second stage of glycolysis from which, the two molecules of pyruvate are obtained as end products of glycolysis. Hence the energy of glycolysis is calculated by considering two molecules of glyceraldehyde 3-phosphate.

Significance of Glycolysis:

  • Glucose - 6 - p is the common intermediate that is required for various metabolic reactions like glycogen synthesis, HMP pathway, etc.

  • Fructose - 6 - P is required for the synthesis of glucosamine.

  • In the HMP pathway for the synthesis of pentose, triose like glyceraldehyde - 3 - P is used.

Energetics of Anaerobic Glycolysis

Anaerobic glycolysis occurs in the absence of oxygen, during insufficiency of oxygen, and in case of the high demand of energy in the muscles, the anaerobic glycolysis pathway occurs. As the RBCs lack mitochondria, they derive energy from lactic acid fermentation. Another example where anaerobic respiration takes place is in the lens of the eye.

Two processes occur under anaerobic glycolysis, they are:

  1. Lactic Acid fermentation: This process occurs in the absence of oxygen in the muscles where lactate is converted into pyruvate with the help of an enzyme called lactate dehydrogenase.

  2. Ethanol Fermentation: In this process, glucose gets converted into ethanol instead of pyruvate. 

Hence we can tell that the end product of anaerobic respiration is lactic acid or ethanol along with the ATP molecules.

Importance of Glycolysis

Glycolysis is the most important pathway, 

  • Most of the energy used by cells comes from glucose.

  • It is the first pathway that is used to convert glucose into energy.

  • It is one of the ancient pathways that is seen as it is used by all living organisms.

  • It is the first main metabolic pathway of cellular respiration that produces energy in the form of ATP.

Evolutionary Significance of Glycolysis

The evolutionary significance of glycolysis includes:

  • Ancient prokaryotes used glycolysis before oxygen was present in the atmosphere.

  • Bacteria produced O2 exclusively from photosynthesis → prokaryotes generate ATP exclusively from glycolysis.

  • Glycolysis is the most widespread metabolic pathway and does not require any membrane-enclosed organelles.

Gluconeogenesis Significance

Gluconeogenesis is a pathway that consists of a series of eleven enzyme-catalyzed reactions. The pathway will begin in either the liver or kidney, in the mitochondria or cytoplasm of those cells, it is dependent on the substrate used.

The gluconeogenesis significance is as follow:

  • When sufficient amounts of carbohydrates are not obtained from diet this process provides the required glucose.

  • By the process of glycogenolysis, the glycogen stored in the adipose tissue and skeletal muscle is converted into glucose.

  • It is used to clear the products of the metabolism of other tissues from the blood.

Energetics of Gluconeogenesis

Energetics of gluconeogenesis are; the six nucleotide triphosphate molecules are hydrolyzed for the synthesis of glucose from pyruvate in gluconeogenesis, whereas only two molecules of ATP are generated in glycolysis in the conversion of glucose into pyruvate. 

Glycolysis is a very important process occurring in nature that is studied under Biology. We all know that living organisms need food for their sustenance.  All animals, be it carnivores or herbivores, obtain their food directly or indirectly from the plants which are in the form of glucose. After the intake of glucose, the metabolic activities performed in the body of animals changes it into actually usable forms. By utilizing the oxygen obtained from the respiration process the glucose is broken down into simpler forms. This breakdown can also occur in the absence of oxygen termed anaerobic glycolysis.

However, the most common type is aerobic respiration in the presence of oxygen and by the use of ATP. This is the only pathway for the availability of energy to perform various activities. 

A glucose molecule consists of six carbon atoms and 6 oxygen atoms and 12 hydrogen atoms. During the chemical breakdown of glucose to molecules of pyruvates are obtained. Several other molecules are also obtained by the process of glycolysis which is also very essential for the performance of various metabolic activities in animal as well as human bodies. For example, fructose is required for glucosamine, and glyceraldehyde is utilized for the synthesis of pentose. 

The students will get to learn about the actual condition and the breakdown of energy pathways for driving this process inside the animal bodies in the higher classes. Refer to the official website of Vedantu or download the app for an elaborate and easy explanation.

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FAQs (Frequently Asked Questions)

1.  Is there any evolutionary significance of Glycolysis?

Life on Earth has developed in millions of years through gradual evolution. The very first creatures to inhabit the planet were unicellular organisms which are also known as eukaryotes. But only after the origin of multicellular organisms such as prokaryotic microorganisms does the complexity of life start to progress. In an oxygen-less atmosphere of those times, these ancient prokaryotes developed the process of Glycolysis. Later this method of obtaining energy to maintain the energy requirements of organisms was passed on to other higher forms of life with evolution. Check out Vedantu’s website or download the app for a comprehensive explanation.

2. Which class books should I refer to get a detailed study on the topic of Glycolysis?

The metabolic activities taking place inside the body of animals including humans are covered under the subject of Biology. Students of CBSE, ICSE, or any other board get introduced to the various life processes in their Science textbooks in lower classes. You can refer to the textbooks available of various publications containing the topic of glucose formation in the junior classes. Although the utilization of glucose by various organisms consuming it and the processes involved is taught in the higher classes. There are also many animated videos to give a better understanding of the subject to the students of any class. You can also refer to the official website of Vedantu or its app for an elaborate and comprehensive explanation for the same.

3. Which is the best Book available in the market for the subject of Biology of 11 Class?

Biology as a subject carries equal importance as other subjects of Class 11 and for the students preparing for the National Eligibility Entrance Examination (NEET) or any other medical entrance exams, it carries more importance. Every chapter and the concepts in it are related and can be very important from the examination point of view. So the students must prepare this subject with full details and attention. The detailed study is supplemented by the reference books available in the market or online. 

4. Is it sufficient for my final exams to learn about the process of Glycolysis through the study materials provided by the Vedantu website?

The website for Vedantu Online Courses has a well-structured and planned study course of all the chapters of any subject for all classes. These study materials are written and compiled by expert teachers which is completely according to the syllabus provided by the Central Board of Secondary Education (CBSE) and the Indian Council of Secondary Education (ICSE). So for the students of CBSE or ICSE, it is a golden opportunity to get their concepts clear and complete the syllabus within the lowest possible time. For further studies, students can refer to the study materials available for other classes as well.

5. What is the price of the Biology course materials for self-studies provided by Vedantu?

The good news for the students who need to prepare for their various term exams and final exams is that they can do so without paying any price. All they need to do is get registered on the portal with some basic information about their class and the exam they are preparing for. The registration is free of cost which will allow you to access the various resources required for your studies. Students can also download these materials which are provided in PDF format and free of cost. They can also get it printed to keep the hard copy of the subject and get help offline. So without wasting any more, get enrolled on Vedantu and step up your preparation!

6. What are the three main steps involved in Glycolysis?

The Main Steps Involved in Glycolysis are:

  • Glucose is trapped and destabilized as it is the main component.

  • The interconvertible three-carbon molecules are generated by the cleavage of six-carbon fructose.

  • ATP is generated.

7. What are the different types of Glycolysis?

There are 2 different types of glycolysis, they are:

  • Aerobic respiration

  • Anaerobic respiration

In aerobic conditions, the pyruvate enters the citric acid cycle and it undergoes oxidative phosphorylation that leads to the net production of 32 ATP molecules. In anaerobic conditions, pyruvate converts to lactate through anaerobic glycolysis.