How is glucose utilized in aerobic respiration?

In aerobic respiration, glucose is broken down to produce ATP, carbon dioxide and water through glycolysis, Krebs cycle, and oxidative phosphorylation.

Aerobic respiration is a process that occurs in the mitochondria of cells, where glucose, a simple sugar, is used to produce energy. This process is crucial for all living organisms as it provides the energy needed for various cellular activities. The process involves three main stages: glycolysis, the Krebs cycle, and oxidative phosphorylation.

Glycolysis is the first stage of aerobic respiration. It takes place in the cytoplasm of the cell and does not require oxygen. In this process, one molecule of glucose, a six-carbon sugar, is split into two molecules of pyruvate, a three-carbon compound. This process also produces a small amount of ATP (adenosine triphosphate), the energy currency of the cell, and NADH, a high-energy electron carrier.

The pyruvate molecules produced in glycolysis are then transported into the mitochondria, where they enter the Krebs cycle (also known as the citric acid cycle or tricarboxylic acid cycle). In the Krebs cycle, each pyruvate molecule is further broken down, releasing carbon dioxide as a waste product. This process also produces more ATP, NADH, and another high-energy electron carrier called FADH2.

The final stage of aerobic respiration is oxidative phosphorylation, which takes place in the inner mitochondrial membrane. Here, the NADH and FADH2 produced in the previous stages donate their high-energy electrons to the electron transport chain. This flow of electrons powers the synthesis of a large amount of ATP. At the end of the electron transport chain, the electrons combine with oxygen (the final electron acceptor) and hydrogen ions to form water.

In summary, glucose is utilised in aerobic respiration to produce ATP, the main energy source for cells. This process also produces carbon dioxide and water as by-products.