Which system provides automatic regulation of internal body functions?

The autonomic nervous system is responsible for the automatic regulation of internal body functions without conscious effort. This system controls involuntary functions such as heart rate, digestion, respiratory rate, and the regulation of sweat glands. It operates autonomously, meaning that it automatically adjusts bodily functions to maintain homeostasis—a stable internal environment—regardless of our awareness or intention.

In contrast, the central nervous system primarily consists of the brain and spinal cord, which processes information and issues commands. The peripheral nervous system connects the central nervous system to the limbs and organs but is not directly involved in the automatic regulation of internal functions. The somatic nervous system, a part of the peripheral nervous system, is responsible for voluntary control of body movements corresponding to skeletal muscles. Thus, it does not regulate internal functions automatically.