Multiple choice The NADPH and ATP from the light-dependent reactions are used to ___________. split water cause RuBP carboxylase to fix carbon dioxide re-form the photosystems convert PGA to PGAL cause electrons to move along their pathways Reveal answer Fill a bubble to check yourself D Correct answer Explanation In the Calvin cycle, ATP and NADPH are used to reduce 3-phosphoglycerate (PGA) into glyceraldehyde-3-phosphate (PGAL/G3P).