Final answer:
Cytochrome c is oxidized by Ero1 with cofactor FMN. This reaction is a part of the electron transport chain in mitochondria.
Step-by-step explanation:
The protein cytochrome c is oxidized by the Ero1 protein with cofactor flavin mononucleotide (FMN); as a result, Ero1 is reduced during this process. Cytochrome c is a heme protein that plays a pivotal role in electron transport chain, where it accepts electrons from Complex III, also known as cytochrome c reductase or cytochrome bc₁ complex, and passes them to Complex IV, cytochrome c oxidase. FMN, derived from vitamin B₂ (riboflavin), is essential for the initial stages of the electron transport chain, specifically within Complex I where it aids in transferring electrons from NADH to the subsequent proteins in the chain.