Final answer:
The sympathetic and parasympathetic nervous systems counteract each other's activity to maintain homeostasis in the body.
Step-by-step explanation:
The sympathetic and parasympathetic nervous systems counteract each other's activity to maintain the body's homeostasis, which is a state of balance.
The sympathetic nervous system prepares the body for stress-related activities, such as increasing the heart rate and dilating air passages in the lungs.
On the other hand, the parasympathetic nervous system returns the body to routine, day-to-day operations, such as slowing down the heart rate and stimulating digestion.