Which one of the following reactions has flavin mononucleotide (FMN) as a coenzyme?
**Core Concept**
Flavin mononucleotide (FMN) is a coenzyme that plays a crucial role in various redox reactions, particularly in the transfer of electrons. It is an essential component of several flavoproteins involved in cellular respiration and energy metabolism.
**Why the Correct Answer is Right**
FMN is a key coenzyme in the electron transport chain, facilitating the transfer of electrons from NADH to oxygen through various flavoproteins, including succinate dehydrogenase and NADH dehydrogenase. The presence of FMN in these enzymes enables the efficient transfer of electrons, ultimately leading to the production of ATP.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because NADH is not directly involved in a reaction with FMN as a coenzyme. NADH is primarily associated with the electron transport chain, where it donates electrons to FMN-containing flavoproteins.
**Option B:** This option is incorrect because FAD (flavin adenine dinucleotide) is a different coenzyme that also plays a role in redox reactions, but it is not the correct answer in this context.
**Option C:** This option is incorrect because the reaction involving succinate dehydrogenase is actually catalyzed by FAD, not FMN.
**Clinical Pearl / High-Yield Fact**
Flavin mononucleotide (FMN) is an essential coenzyme in the electron transport chain, facilitating the transfer of electrons from NADH to oxygen. This process is crucial for the production of ATP in aerobic respiration.
**Correct Answer:** C. Succinate dehydrogenase