Proton pumps in companion cells

  1. pump water into the phloem
  2. make ATP
  3. pump sucrose directly into the xylem
  4. use ATP to pump H⁺ out of the cell
Answer

D) use ATP to pump H⁺ out of the cell

They create the proton gradient. AS & A Level Biology · Topic 7 Transport in Plants · 7.2 Transport mechanisms

Biology MCQ · More A Level Biology: Transport in plants MCQs · Practise