Final answer:
The Krebs cycle occurs in the mitochondrial matrix and involves converting acetyl CoA into carbon dioxide and high-energy molecules such as ATP, NADH, and FADH2. These molecules are essential for the electron transport chain and the production of ATP through oxidative phosphorylation.
Step-by-step explanation:
During the Krebs cycle, which takes place in the mitochondrial matrix, pyruvate from glycolysis is transformed into acetyl CoA. This acetyl CoA then enters the Krebs cycle where it undergoes a series of reactions that result in the production of high-energy molecules: ATP, NADH, and FADH2. Importantly, the cycle results in the release of carbon dioxide and the generation of energy-carrying molecules. The NADH and FADH2 produced will subsequently feed into the electron transport chain, which is a crucial step in the synthesis of a large quantity of ATP through oxidative phosphorylation.
During each turn of the Krebs cycle, the initial six-carbon citrate molecule is transformed into a four-carbon oxaloacetate molecule, ready to begin the cycle again. Throughout this transformation, carbon molecules are released as CO2 and energy is captured in the form of one ATP, one FADH2, and three NADH per citrate molecule. These energy carriers then transport electrons to the electron transport chain, where hydrogen ions are pumped across the mitochondrial membrane contributing to the production of ATP.