Answer;
-Autonomic nervous system
Step-by-step explanation;
-The autonomic nervous system regulates a variety of body process that take place without conscious effort. The autonomic system is the part of the peripheral nervous system that is responsible, as the name implies, for regulating involuntary body functions such as heartbeat, blood flow, breathing, and digestion.
-It also controls some of the muscles within the body. We are often unaware of the ANS because it functions involuntary and reflexively. For example, we do not notice when blood vessels change size or when our heart beats faster.