Final answer:
FAD and FADH2 are coenzymes involved in oxidation-reduction reactions, accepting electrons and hydrogen ions. FMN and FMNH2 participate in electron transport chain reactions, passing on electrons to iron-sulfur clusters and coenzyme-Q for ATP production.
Step-by-step explanation:
FAD (Flavine Adenine Dinucleotide) and FADH2 (reduced form of FAD) are coenzymes involved in oxidation-reduction reactions. They function by accepting electrons and hydrogen ions (H+) during these reactions. FAD/FADH2 play a crucial role in energy extraction from sugars in cells.
Similarly, FMN (Flavin Mononucleotide) and FMNH2 (reduced form of FMN) are also coenzymes that participate in electron transport chain reactions. FMNH2 accepts electrons from NADH or FADH2 and transfers them to iron-sulfur clusters and then to coenzyme-Q, aiding in the production of ATP.