During cellular respiration, glucose undergoes a series of metabolic pathways in the presence of oxygen. Here’s a step-by-step explanation:
1. Glycolysis:
- The process begins with glycolysis, where one molecule of glucose (C₆H₁₂O₆) is broken down into two molecules of pyruvate. This occurs in the cytoplasm of the cell and results in the production of ATP and NADH.
2. Pyruvate Oxidation:
- The pyruvate molecules enter the mitochondria, where they are converted into Acetyl-CoA. This process releases carbon dioxide (CO₂) and produces more NADH.
3. Citric Acid Cycle (Krebs Cycle):
- Acetyl-CoA enters the citric acid cycle. During this cycle, further breakdown of molecules takes place, releasing more CO₂ and generating NADH and FADH₂, along with a small amount of ATP.
4. Electron Transport Chain (ETC):
- NADH and FADH₂ donate electrons to the electron transport chain in the inner mitochondrial membrane. As electrons move through the chain, they facilitate the pumping of protons across the membrane, creating a proton gradient.
5. ATP Synthesis:
- The proton gradient created by the ETC powers ATP synthase, which synthesizes ATP from ADP and inorganic phosphate. This is called oxidative phosphorylation.
So, during cellular respiration, the energy stored in the bonds of glucose is systematically released and used to produce ATP. In summary:
What happens to the energy in the bonds in glucose?
The energy is transferred to ATP.
