What is this final stage of cellular respiration called where the most ATP molecules are made?
http://www.biology.iupui.edu/biocourses/N100/2k4ch7respirationnotes.html
Oxidative phosphorylation
during the ETC
The final stage of cellular respiration where the most ATP molecules are made is called the Electron Transport Chain (ETC).
To understand why this stage produces the most ATP, let me explain a bit about cellular respiration. Cellular respiration is a complex process that occurs in the mitochondria of cells. It involves the breakdown of glucose and other molecules to produce ATP, which is the main energy currency of cells.
The first three stages of cellular respiration, namely glycolysis, pyruvate oxidation, and the citric acid cycle, generate a small amount of ATP through substrate-level phosphorylation. However, the majority of ATP production occurs during the final stage - the Electron Transport Chain.
Here's how the Electron Transport Chain works and how it leads to a high production of ATP:
1. The Electron Transport Chain is embedded in the inner membrane of the mitochondria. It consists of a series of protein complexes (including protein carriers and enzymes) that transfer electrons extracted from glucose and other molecules.
2. The electrons are derived from the energy-rich molecules NADH and FADH2, which were produced in the earlier stages of cellular respiration.
3. The electron carriers in the Electron Transport Chain pass the electrons through a series of redox reactions. This creates a gradient of protons (H+) across the inner mitochondrial membrane.
4. The proton gradient created by the electron transfer generates a significant amount of potential energy. This energy is then used by an enzyme called ATP synthase, which is the key player in ATP production.
5. ATP synthase utilizes the potential energy stored in the proton gradient to facilitate the synthesis of ATP from ADP (adenosine diphosphate) and inorganic phosphate (Pi). As the protons move through ATP synthase, it drives the mechanical rotation of its molecular components, resulting in the production of ATP.
Overall, the Electron Transport Chain serves as a final electron acceptor and acts as a prolific generator of ATP. It efficiently converts the potential energy derived from the electron transfer into chemical energy in the form of ATP. This is why the Electron Transport Chain is known as the stage where the most ATP molecules are made during cellular respiration.