Clonal selection is when

  1. lymphocytes with receptors complementary to an antigen are activated
  2. all lymphocytes divide
  3. phagocytes engulf pathogens
  4. antibodies clump bacteria
Answer

A) lymphocytes with receptors complementary to an antigen are activated

Only matching lymphocytes are selected. AS & A Level Biology · Topic 11 Immunity · 11.1 The immune system

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