FADH2 enters the respiratory chain through which complex?: (A) I, (B) II, (C) III, (D) IV
Answer is B. In Complex II (succinate-Q reductase), FADH2 is formed during the conversion of succinate to fumarate in the citric acid cycle and electrons are then passed several Fe-S centers to Q. Reference: Harper; 30th edition; Page no: 128