Problem: Describe in detail how a neural impulse is propagated? be sure to define and use all of the following terms in your discussion: action potential, axon hillock, axon, calcium channels, dendrite, depolarization, hyper-polarization, neurotransmitter, post- synaptic receptor sites, refractory period, resting potential, sodium- potassium pump, terminal button, threshold, vesicle, voltage dependent on channels.