Explain why the sympathetic division of the ANS has more widespread and longer-lasting effects than the parasympathetic division
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A single sympathetic preganglionic fiber has many axon collaterals (branches) and synapses with 20 or more postganglionic neurons, whereas a parasympathetic preganglionic neurons synapses with only 4 or 5 postganglionic neurons. The sympathetic neurotransmitter, norepinephrine is broken down more slowly than acetylcholine, so postganglionic cells are stimulated longer. The sympathetic division also stimulates release of catecholamines (mostly epinephrine) from the adrenal medulla, thus enhancing the sympathetic effects via the endocrine system. Also, more visceral effectors have receptors for catecholamines (norepinephrine and epinephrine) than for acetylcholine.
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