Final answer:
The immediate products of NADH bond cleavage are NAD+ and free electrons, which participate in the electron transport chain.
Step-by-step explanation:
The high-energy bond in NADH is cleaved when it donates a pair of electrons to the electron-transport chain. The immediate products of this bond cleavage are NAD+ and free electrons, which are then used in the electron-transport chain. The released electrons move through a series of complexes in the electron transport chain, which leads to the pumping of protons across the inner mitochondrial membrane, thereby creating a proton gradient that drives the synthesis of ATP.
During this process, the enzyme flavin mononucleotide (FMN) initially accepts the electrons from NADH, becoming FMNH₂ before passing the electrons along to the iron-sulfur clusters and eventually to coenzyme-Q (ubiquinone), which becomes ubiquinol (QH₂).