The diagram shows a chemical synapse.
A clinical drug, ziconotide, is a selective blocker of the voltage-gated calcium channels (structure JJJ) in the pre-synaptic membrane. Which of the following statements describes the direct effect of ziconotide on synaptic transmission?
It prevents the depolarisation of the pre-synaptic membrane.
It prevents the release of neurotransmitter from structure LLL.
It blocks the binding of neurotransmitter to structure KKK.
It causes continuous hyperpolarisation of the post-synaptic membrane.