the ________ nervous system is responsible for responses such as pupil dilation, increased heart rate, and increased respiration.

The nervous system responsible for responses such as pupil dilation, increased heart rate, and increased respiration is the sympathetic nervous system. It is part of the autonomic nervous system, which controls involuntary physiological functions. The sympathetic nervous system activates the "fight or flight" response, preparing the body for stressful or emergency situations by dilating the pupils, increasing heart rate, and increasing respiration to supply more oxygen to the body.