Answer: The system that helps calm me down after am upset is the PARASYMPATHETIC NERVOUS SYSTEM which is one of the system integrated within my brain.
Step-by-step explanation:
The adult human BRAIN is made up mainly of neurones. There are more than a thousand neurons in the brain which are the basic structural units of the nervous system. There are two integrated systems in the brain:
--> The sympathetic nervous system and
--> Parasympathetic nervous system.
In the sympathetic nervous system, it's effects dominates in times of emergency or prolonged exertion, that is, they prepare the body for stress. It innervates most of the internal organs and has a slightly wider distribution than parasympathetic nervous system.
The PARASYMPATHETIC NERVOUS SYSTEM has it's effects dominate during normal relaxed conditions. They also innervates most of the internal organs that are innervated by sympathetic nervous system. Therefore it opposes the activities of the sympathetic nervous system.
For example, in emergency stressful situation, the sympathetic nervous system causes the heart activities to increase. This returns to normal once the emergency is over through the activities of the PARASYMPATHETIC NERVOUS SYSTEM.