MDCAT Biology MCQ #516

Under which environmental conditions does photorespiration most likely occur in C3 plants, reducing the efficiency of the Calvin cycle?

MDCAT Biology MCQ #516

  1. Question 1

    Q1. Under which environmental conditions does photorespiration most likely occur in C3 plants, reducing the efficiency of the Calvin cycle?

    • A) High CO2 and low O2
    • B) Low temperature and high humidity
    • C) High O2 and low CO2
    • D) High CO2 and high temperature

    Answer: High O2 and low CO2

    Explanation: Photorespiration occurs when Rubisco fixes O2 instead of CO2, leading to the production of phosphoglycolate and 3-PGA.