What Happens in a Chemical Synapse?

step 9

may open sodium channels

step 4

Calcium goes into axon terminal

step 3

Calcium ion channels open in axon terminal

what else can happen to the MP in the post-synaptic neuron?

If potassium channels open, then potassium ions released causes the MP to become more negative (aka cannot reach threshold ) = IPSP

step 10

if sodium channels release sodium into the post-synaptic neuron, this causes the membrane potential to become more positive = EPSP

step 6

Release of neurotransmitters (all types) into synaptic cleft

step 2

AP hits axon terminal

step 1

AP travels down axons of PRESYNAPTIC neuron

step 5

Exocytosis of synaptic vesicles containing neurotransmitters

step 8

Neurotransmitters bind to receptors on dendrites of POST-SYNAPTIC neuron

step 7

Neurotransmitters diffuse across synaptic cleft