MDCAT Biology MCQ #463

During oxidative phosphorylation, electrons are passed through a series of cytochromes. What is the correct sequence of these carriers in the ETC?

MDCAT Biology MCQ #463

  1. Question 1

    Q1. During oxidative phosphorylation, electrons are passed through a series of cytochromes. What is the correct sequence of these carriers in the ETC?

    • A) Cyt b -> Cyt c -> Cyt a -> Cyt a3
    • B) Cyt a -> Cyt a3 -> Cyt b -> Cyt c
    • C) Cyt c -> Cyt b -> Cyt a3 -> Cyt a
    • D) Cyt b -> Cyt a -> Cyt c -> Cyt a3

    Answer: Cyt b -> Cyt c -> Cyt a -> Cyt a3

    Explanation: The PTB sequence is cyt b, cyt c, cyt a, then cyt a3; cyt a3 is the final carrier before oxygen.