Protons are pumped into the thylakoid space using energy from

  1. ATP hydrolysis
  2. electrons passing along the electron transport chain
  3. the Calvin cycle
  4. photolysis only
Answer

B) electrons passing along the electron transport chain

ETC energy pumps H⁺. AS & A Level Biology · Topic 13 Photosynthesis · 13.1 Photosynthesis as an energy transfer process

Biology MCQ · More A Level Biology: Photosynthesis MCQs · Practise