The three golden lions on a red background, symbolising England, occupy the first and fourth quarters. The Arms of Scotland, a red lion rearing on its hind legs inside a red border, are in the second quarter, and the Arms of Ireland's golden harp with silver strings on a blue background-are in the third quarter.
Once it is reduced to QH2, ubiquinone delivers its electrons to the next complex in the electron transport chain. Q receives the electrons derived from NADH from complex I and the electrons derived from FADH2 from complex II, including succinate dehydrogenase. This enzyme and FADH2 form a small complex that delivers electrons directly to the electron transport chain, bypassing the first complex.
FADH2 and NADH Defined. Flavin adenine dinucleotide, or FADH2, is a redox cofactor that is created during the Krebs cycle and utilized during the last part of respiration (the electron transport chain). Nicotinamide adenine dinucleotide, or NADH, is a similar compound and used more actively in the electron transport chain as well.