Synapses- junctions or connections between two neurons.
- A nerve impulse arrives at the end of the presynaptic membrane and causes CO2 to enter in the synaptic knob.
- Vesicles containing neurotransmitters move towards the presynaptic membrane, fuse with it and release their content into the synaptic cleft.
- ACH diffuses across the synaptic cleft and reaches the receptors at the post synaptic membrane.
- ACH fuses with the post synaptic membrane.
- The sodium channels open and the postsynaptic membrane is depolarised.
EPSP generated = signal is transmitted.
EPSP:
excitatory, stimulating, less than -70 mV (less negative due to the depolarisation)
IPSP: inhibitory postsynaptic potential.
Higher than -70 mV du to hyper-polarisation.