Now, when the action potential is carried all the way to the exxon terminal of the post ganglionic cell at the synapse between our exxon terminal the post ganglionic cell and the cell of our effector organ. In this case, we use a different neurotransmitter. We either use Epinephrine or we use Norepinephrine. So once again, in the case of the sympathetic nervous system, every single pre ganglionic cell begins in our spinal cord and we'll see this is not the case in the parasympathetic system. Now, there is an exception to this rule. So inside the sympathetic nervous system, we usually have two of these neurons.