Human Physiology Sympathetic Nervous System

Question :

let's talk about the SNS (Sympathetic Nervous System) and PNS (Parasympathetic nervous system). Please describe both systems and give examples of action items that represent each. What is the main function of each system? What are the main components that make up each system? Give examples that demonstrate the difference between SNS and PNS systems.

Answer :

Sympathetic Nervous System 

The sympathetic nervous system is a part of the automatic nervous system that includes mainly adrenergic fibers that help in depressing secretion, decreasing contractility as well as the tone of mouth muscles. It also increases heart rate. The main function of the sympathetic nervous system is to prepare a body or individual to deal with an emergency situation (Karvonen et al., 2016). It fights with danger or helps in fighting with danger such as an increase in heart rate, dilation of pupils, bronchial dilation, etc. It also regulates body temperature in order to maintain heat production and blood flow to the skin. It also regulates the cardiovascular system. The main components of the sympathetic nervous system are peri-arterial plexuses, all spinal nerves, blood vessels, sweat glands, viscera, and arrector pili.

Parasympathetic Nervous System

It is one of the divisions of the automatic nervous system. It is also called the rest as well as the digestive system. It conserves energy as it relaxes sphincter muscles, enhances gland activity, intestinal activity, and reduces the heart rate. The main function of the parasympathetic nervous system is to control blood pressure under resting conditions. It also controls heart rate under resting conditions. It improves the process of digestion (Liu et al., 2020). It also stimulates the process of urination. The key components of the parasympathetic system are sacral as well as cranial spinal nerves. 

The key difference between the sympathetic nervous system and parasympathetic nervous system is that the SNS prepares a body to fight with the potential danger while PSN helps a body to restore to a composed and calm state from overworking. 

References 

Karvonen, A., Kykyri, V. L., Kaartinen, J., Penttonen, M., & Seikkula, J. (2016). Sympathetic nervous system synchrony in couple therapy. Journal of marital and family therapy, 42(3), 383-395.

Liu, Y., Jansen, H. J., & Rose, R. A. (2020). Impaired Parasympathetic Nervous System Regulation of Heart Rate and Sinoatrial Node Function in Type 2 Diabetes Mellitus. Biophysical Journal, 118(3), 102a.