Glycolysis: What is it? Function, Steps, Types and Differences

It is the main pathway for glucose metabolism and is produced in the cytosol of all cells.


Glycolysis produces energy in the form of adenosine triphosphate (ATP). During the process, glucose is oxidized to lactate or pyruvate.

Steps of glycolysis

Glycolysis is an extramitochondrial pathway carried by a group of eleven enzymes. Glucose is converted to pyruvate in 10 steps by glycolysis. The glycolytic pathway can be divided into two phases:

Preparatory phrase

This phase is also called the glucose activation phase. In the preparatory phase of glycolysis, two ATP molecules are inverted, and the hexose chain splits into two triose phosphates.

During this, glucose phosphorylation and its conversion to glyceraldehyde-3-phosphate take place. Steps 1, 2, 3, 4, and 5 are called the preparatory phase.

Payment phase

This phase is also called the energy extraction phase. During this phase, the conversion of glyceraldehyde-3-phosphate to pyruvate and the coupled formation of ATP takes place.

Because glucose splits to produce two molecules of D-Glyceraldehyde-3-phosphate, each step in the payment phase occurs twice per glucose molecule. Actions after 5 constitute the payment phase.


Types of glycolysis

There are two different pathways by which the glycolysis process takes place. One is aerobic, and the other is anaerobic.

Aerobic glycolysis: occurs when oxygen is abundant. The end product is pyruvate and the production of eight ATP molecules.

Anaerobic glycolysis: occurs when oxygen is scarce. The end product is lactate along with the production of two ATP molecules.

Glycolysis through aerobic glycolysis occurs when oxygen and hydrogen atoms join together to break down glucose and facilitate energy exchange.

It is a metabolic pathway that involves the transformation of glucose into pyruvate and the subsequent conversion of pyruvate to lactate in the absence of oxygen.

Anaerobic glycolysis transforms glucose into lactate when limited amounts of oxygen (O2) are available. This type of glycolysis is just 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 system is dominant during the maximal effort from approximately 10 to 30 seconds. It is replenished very rapidly during this period and produces 2 ATP molecules per glucose molecule or about 5% of the energy potential of glucose (38 ATP molecules).

Analysis generation is the primary means of energy production in organisms with a high concentration in the atmosphere and an older form of energy production in cells.

Differences between anaerobic and aerobic glycolysis

The main difference between anaerobic and aerobic glycolysis is that sugar is not entirely broken down in the latter. Instead, it turns into lactic acid or ethyl alcohol. However, many animals and plants use the anaerobic pathway to produce ATP.

Another difference between aerobic and anaerobic glycolysis is the presence or absence of oxygen. If oxygen is involved, the process is aerobic; otherwise, the process becomes anaerobic without oxygen.

The by-products of each process are also involved. Aerobic glycolysis has carbon dioxide and water as by-products, while anaerobic glycolysis generates results such as ethyl alcohol in plants and lactic acid in animals.

Aerobic glycolysis is used for the first time in any activity, and the phosphocreatine system helps during activities that last no more than thirty seconds. Anaerobic glycolysis kicks in during long-lasting activities, assisting the body’s muscles using energy.