Depolarisation during an action potential is caused by

  1. K⁺ ions diffusing out
  2. the Na⁺/K⁺ pump
  3. Ca²⁺ ions leaving
  4. Na⁺ ions diffusing into the axon through voltage-gated channels
Answer

D) Na⁺ ions diffusing into the axon through voltage-gated channels

Na⁺ influx depolarises. AS & A Level Biology · Topic 15 Control and Coordination · 15.1 Control and coordination in mammals

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