The nurse is explaining the workings of selective serotonin reuptake inhibitors to a client with a diagnosis of depression. within the teaching, the nurse mentions that in the nervous system, the transmission of information by neurotransmitters is:

Synaptic signaling is the answer.  It is the same to paracrine signaling but there is a something different in structure called the synapse between the two cell originating and the receiving the signal for example between a neuron and the muscle that is controlled by neural activity. It only happens between cells with synapse. 

protons have a positive charge and are located inside of the nucleus. electrons have a negative charge and are located outside of the nucleus. neutrons have a neutral charge and are located inside of the nucleus.