Expansins are proteins that

  1. loosen links between cellulose microfibrils at low pH
  2. make auxin
  3. digest starch
  4. pump protons
Answer

A) loosen links between cellulose microfibrils at low pH

They allow wall stretching. AS & A Level Biology · Topic 15 Control and Coordination · 15.2 Control and coordination in plants

Biology MCQ · More A Level Biology: Control and coordination MCQs · Practise