What changes in the body might indicate the parasympathetic nervous system is activated?

What changes in the body might indicate the parasympathetic nervous system is activated?

• A. Increased heart rate
• B. Decreased blood pressure
• C. Decreased pupil size
• D. Increased blood glucose levels

Answer: (C)

When the parasympathetic nervous system is activated, it is primarily responsible for promoting a state of rest and relaxation in the body, often referred to as the "rest and digest" response. One indication of this activation can be seen in the decrease in pupil size, also known as miosis. This response is linked to the body's focus on conserving energy and facilitating functions associated with digestion and recovery rather than the "fight or flight" responses driven by the sympathetic nervous system, which would cause pupil dilation to enhance vision and alertness. In this context, decreased pupil size reflects the activation of the parasympathetic system and is indicative of body systems calming down and returning to a more relaxed state. During this phase, functions such as digestion and elimination are prioritized, and various physiological responses shift accordingly. Consequently, while changes such as increased heart rate and blood glucose levels align with sympathetic activation, and a decrease in blood pressure is not necessarily a direct indicator of parasympathetic functioning by itself, the reduction in pupil size represents a clear, significant sign of parasympathetic activity in the body, supporting the concept of relaxation and restoration.

When the parasympathetic nervous system is activated, it is primarily responsible for promoting a state of rest and relaxation in the body, often referred to as the "rest and digest" response. One indication of this activation can be seen in the decrease in pupil size, also known as miosis. This response is linked to the body's focus on conserving energy and facilitating functions associated with digestion and recovery rather than the "fight or flight" responses driven by the sympathetic nervous system, which would cause pupil dilation to enhance vision and alertness.

In this context, decreased pupil size reflects the activation of the parasympathetic system and is indicative of body systems calming down and returning to a more relaxed state. During this phase, functions such as digestion and elimination are prioritized, and various physiological responses shift accordingly.

Consequently, while changes such as increased heart rate and blood glucose levels align with sympathetic activation, and a decrease in blood pressure is not necessarily a direct indicator of parasympathetic functioning by itself, the reduction in pupil size represents a clear, significant sign of parasympathetic activity in the body, supporting the concept of relaxation and restoration.