The sympathetic and parasympathetic nervous systems operate in tandem, producing antagonistic effects to maintain homeostasis. Their contrasting influences on various bodily organs include:

• Pupils: The sympathetic system dilates pupils, while the parasympathetic system constricts them.
• Salivation: Sympathetic activity inhibits salivation, whereas parasympathetic activity stimulates it.
• Heart Rate: The sympathetic division increases heart rate, but the parasympathetic division slows it down.
• Bronchi: The sympathetic nervous system dilates bronchi, in contrast to the parasympathetic system which constricts them.
• Digestion: Sympathetic activation inhibits digestion, while parasympathetic activation stimulates it.
• Liver and Bile: The sympathetic system stimulates the breakdown of glycogen; the parasympathetic system stimulates bile secretion.
• Adrenal Gland: Adrenaline and noradrenaline secretion is stimulated by the sympathetic system.
• Bladder: Contraction of the bladder is inhibited by the sympathetic system, whereas it is caused to contract by the parasympathetic system.