Multiple choice

The number of ATP and NADH2 molecules required to fix one molecule of CO2 during a dark reaction are

  1. 2 and 3 respectively

  2. 3 and 3 respectively

  3. 2 and 2 respectively

  4. 3 and 2 respectively

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Fixing one CO2 in the Calvin cycle consumes 3 ATP and 2 NADPH. This energy powers carbon reduction and RuBP regeneration.