The is the part of the autonomic nervous system that arouses the body to mobilize it for action and thus is involved in the experience of stress.

sympathetic nervous system

Explanation:

The sympathetic nervous system is one of the parts of the autonomic nervous system that controls involuntary and unconscious body movement functions such as heart rate, perspiration rate, blood pressure and body metabolism.

The sympathetic nervous system is triggered to control the involuntary body functions when the body perceives a threat or distress. When his happen, the sympathetic nervous system initiates and increases the body metabolism to produce responses referred to as the “fight or flight” response thereby increasing body alertness. Such responses include increased heart rate, increased perspiration and breath rate, raise in blood sugar level etc .

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not always but somethings can be reproduced in a laboratory.