ANSWER: The events occuring in Complex I in order are 3, 2, 1, 4 NADH is oxidized to NAD+ by reducing FMN to FMNH2 while oxidising Fe+2 to Fe+3 for the electron transport. Finally the CoQ is reduced to CoQH2 after which the electron enters in Complex II Solution ANSWER: The events occuring in Complex I in order are 3, 2, 1, 4 NADH is oxidized to NAD+ by reducing FMN to FMNH2 while oxidising Fe+2 to Fe+3 for the electron transport. Finally the CoQ is reduced to CoQH2 after which the electron enters in Complex II.