Which part of the nervous system controls involuntary actions like heart rate and digestion?

The Autonomic Nervous System is responsible for regulating involuntary actions in the body, specifically functions such as heart rate, digestion, and respiratory rate. This system operates without conscious control, allowing the body to maintain homeostasis and respond to internal and external stimuli automatically. It consists of two main branches: the sympathetic nervous system, which prepares the body for stressful or emergency situations, and the parasympathetic nervous system, which promotes relaxation and conserves energy during rest.

In the context of heart rate, the autonomic nervous system adjusts the rate and strength of heart contractions based on the body's immediate needs, such as during exercise or stress. For digestion, it regulates the activity of the stomach and intestines to optimize nutrient absorption and processing.

The Central Nervous System, which includes the brain and spinal cord, is primarily responsible for processing information and initiating voluntary responses. The Somatic Nervous System controls voluntary movements of skeletal muscles, allowing for conscious control over actions like walking or picking up objects. Thus, the Autonomic Nervous System is clearly defined as the part that handles involuntary physiological functions.