MDCAT Biology MCQ #225

A researcher compares aerobic respiration and photosynthesis. In the light-dependent reactions of photosynthesis, which molecule serves as the ultimate source of electrons?

MDCAT Biology MCQ #225

  1. Question 1

    Q1. A researcher compares aerobic respiration and photosynthesis. In the light-dependent reactions of photosynthesis, which molecule serves as the ultimate source of electrons?

    • A) Water
    • B) Glucose
    • C) Carbon dioxide
    • D) Oxygen

    Answer: Water

    Explanation: Water provides electrons for PSII in photosynthesis. Option B is incorrect because glucose is the product of photosynthesis, not the electron donor.