What is a common property of a neurotransmitter

Question

Quizplus · Accepted Answer

Neurotransmitters are usually synthesized in the cell body of the neuron and then transported to the synaptic terminals where they are stored in vesicles. When an action potential reaches the terminal, these vesicles release their contents into the synapse, where they bind to receptors on the postsynaptic neuron, either exciting or inhibiting its firing. Therefore, choice B is the common property of a neurotransmitter. 
Choices A, C, and D are incorrect because neurotransmitters are not synthesized in the pituitary gland, they are not released when the neuron is at rest, and they can be either excitatory or inhibitory.

What Is a Common Property of a Neurotransmitter