Final answer:
Glutamate is the neurotransmitter that causes a depolarizing effect on the post-synaptic membrane, distinguishing it as an excitatory neurotransmitter in the CNS.
Step-by-step explanation:
The neurotransmitter that elicits a depolarizing effect on the post-synaptic membrane is glutamate. Glutamate is the most prevalent excitatory neurotransmitter in the central nervous system (CNS), and its receptors, when activated, permit the influx of positively charged ions into the postsynaptic neuron, leading to depolarization. This is in contrast to neurotransmitters such as GABA and glycine, which are considered inhibitory since their receptors typically cause hyperpolarization.