Final answer:
The reactants of the formation of Acetyl-CoA are pyruvate and CoA, with the products being acetyl-CoA, NADH, and CO2. In the Krebs cycle, acetyl-CoA combines with oxaloacetate to produce citrate, leading to the generation of ATP, NADH, FADH2, and the regeneration of oxaloacetate. ATP is synthesized during the Krebs cycle by substrate-level phosphorylation.
Step-by-step explanation:
Acetyl-CoA is formed from the oxidation of pyruvate and is a key reactant in the Krebs cycle. During this process, each molecule of pyruvate is decarboxylated to form acetyl-CoA, producing one molecule of NADH and releasing one molecule of CO2 as a byproduct. The formation of Acetyl-CoA occurs in the mitochondrial matrix, an essential step before the Krebs cycle can begin.
Once formed, acetyl-CoA enters the Krebs cycle by condensing with oxaloacetate to form citrate. The cycle involves a series of reactions that result in the regeneration of oxaloacetate and the production of ATP, NADH, and FADH2. ATP is synthesized in the Krebs cycle through substrate-level phosphorylation. Overall, each turn of the cycle results in the production of three NADH, one FADH2, and one ATP (or GTP) molecule, while two molecules of CO2 are released. Given that each molecule of glucose yields two pyruvates during glycolysis, the Krebs cycle turns twice for each glucose molecule.
The electron carriers NADH and FADH2 produced in the Krebs cycle hold much of the energy from the original glucose molecule. This stored energy in NADH and FADH2 will be used in the electron transport chain to produce a significant amount of ATP through oxidative phosphorylation.