question_answer 15)

  Resting membrane potential is maintained by (a) hormones                    (b) neurotransmitters    (c) ion pumps                    (d) None of these

Answer:

                  (c) The ionic gradients across the resting membrane are maintained by the active transport of ions by the sodium-potassium-pumps (or ion pumps) which transport 3 outward for every  into the cell.