* NADH: Nicotinamide adenine dinucleotide (NAD+) is reduced to NADH, carrying high-energy electrons that will be used in the electron transport chain to generate ATP. Three molecules of NADH are produced per cycle.
* FADH2: Flavin adenine dinucleotide (FAD) is reduced to FADH2, also carrying high-energy electrons for the electron transport chain. One molecule of FADH2 is produced per cycle.
* GTP: Guanosine triphosphate (GTP) is a high-energy molecule similar to ATP. One molecule of GTP is produced per cycle, which can be readily converted to ATP.
While the Krebs cycle does not directly produce ATP, it provides the essential components (NADH and FADH2) for the electron transport chain, where the majority of ATP is generated.
