Final answer:
Inhibitory neurotransmitters, like GABA, bind to receptors that open ion channels leading to hyperpolarization of the postsynaptic membrane, which makes neurons less likely to fire an action potential. Examples of inhibitory neurotransmitters include GABA and serotonin.
Step-by-step explanation:
Inhibitory neurotransmitters are chemical messengers that prevent the firing of action potentials in the postsynaptic neuron. They operate by binding to specific receptors on the postsynaptic cell that typically lead to the opening of ligand-gated ion channels. When inhibitory neurotransmitters, such as GABA, bind to these receptors, channels open that allow negatively charged ions, like Cl-, to enter the cell. This influx of negative ions causes hyperpolarization of the postsynaptic membrane, increasing the internal negativity relative to the outside and therefore making it less likely for an action potential to occur, as a higher level of depolarization is now required to reach the threshold.
Some examples of inhibitory neurotransmitters are GABA and serotonin. GABA operates by opening Cl- channels, while serotonin has a variety of mechanisms depending on the type of receptor it binds to.