Which system is responsible for involuntary control of heart rate and digestion?

The autonomic nervous system is the correct answer because it is responsible for controlling involuntary bodily functions, including heart rate and digestion. This system operates automatically without conscious effort, regulating essential processes that sustain life. It has two main branches: the sympathetic and parasympathetic nervous systems, which work together to maintain homeostasis.

For instance, during stress or physical activity, the sympathetic nervous system speeds up the heart rate and slows digestion to prioritize energy to muscles. In contrast, the parasympathetic system promotes a state of rest, slowing the heart rate and enhancing digestion. Together, these components of the autonomic nervous system ensure that the body can respond appropriately to different situations without requiring conscious thought.

The other systems mentioned do not perform these specific involuntary functions. The somatic nervous system, for example, is responsible for voluntary control of body movements through skeletal muscles. The peripheral nervous system, while it encompasses both the autonomic and somatic systems, does not specifically manage involuntary functions alone, which is the key focus of the autonomic nervous system. The sympathetic nervous system, though, is just a part of the autonomic system and does not encompass its full range of functions.