Which of the following is a major inhibitory neurotransmitter? a. acetylcholine b. glutamate c. norepinephrine d. gaba (gamma-aminobutyric acid)

Answer:  D. GABA (gamma-aminobutyric acid).

Explanation:

Neurotransmitters are chemical messengers that cross the synaptic gaps between neurons and thus, relay the message from one neuron to another. Based on the response they produce, neurotransmitters can be inhibitory or excitatory in nature. An inhibitory neurotransmitter is the one decreases the action potential producing ability of the neuron whereas the excitatory neurotransmitter does the opposite. Example of an excitatory neurotransmitter is glutamate.GABA is the major inhibitory neurotransmitter which is found in the adult brain whereas glycine is another inhibitory neurotransmitter that acts at the spinal cord.