This page outlines the coordination of cellular activities in animals through the endocrine and nervous systems, highlighting the contrasting speed and scope of hormonal and neurotransmitter responses...This page outlines the coordination of cellular activities in animals through the endocrine and nervous systems, highlighting the contrasting speed and scope of hormonal and neurotransmitter responses. It details the role of various neurotransmitters, including excitatory and inhibitory effects, and their clearance from synapses.