Presynaptic cell

 The presynaptic cell exclusively contains neurotransmitters such as acetyl choline and glutamate, stored in vesicles. When an action potential arrives in the presynaptic cell, voltage gated Ca2+ channels open allowing for the diffusion of Ca2+ ions into the cell causing the vesicles to undergo exocytosis, emptying their contents into the synaptic cleft. These can the bind to receptors on the postsynaptic membrane .