Difference Between Sympathetic And Parasympathetic Nervous System: Overview, Function
The Autonomic Nervous System controls involuntary actions. It has two parts - the Sympathetic Nervous System and the Parasympathetic Nervous System. The Sympathetic Nervous System prepares the body for “fight or flight”. The Parasympathetic Nervous System helps in rest and digestion. Together, the sympathetic and parasympathetic nervous systems maintain balance and support homeostasis in the nervous system.
This Story also Contains
- Introduction of the Autonomic Nervous System (ANS)
- Sympathetic vs Parasympathetic Nervous System Comparison Table
- Sympathetic Nervous System (SNS)
- Parasympathetic Nervous System (PNS)
- Role of Sympathetic and Parasympathetic Nervous System in Homeostasis
- Fight or Flight vs Rest and Digest Response Explained
- Sympathetic vs Parasympathetic NEET MCQs
- Recommended Video on the Sympathetic vs Parasympathetic Nervous System
The neural control and coordination functions of the sympathetic nervous system include a faster heartbeat, higher blood pressure, and more energy. The functions of the parasympathetic nervous system include a slower heartbeat, digestion, and recovery. The difference between sympathetic and parasympathetic nervous systems is clear- one excites, the other calms. Learn the autonomic nervous system (ANS) origin, structure, functions, and key differences with examples. Includes comparison table, interactions, and NEET MCQs.
Introduction of the Autonomic Nervous System (ANS)
The autonomic nervous system is a part of the peripheral nervous system, controlling the involuntary activities of the body. It controls heart rate, digestive rate, respiratory rate, and pupillary response. It works at a subconscious level. It is divided into
Sympathetic Nervous System
Parasympathetic Nervous System
The sympathetic and parasympathetic systems have different roles in maintaining the major activities within the body that help keep the person alive and comfortable. The sympathetic system gets the human body ready for stressful situations, while the parasympathetic system gets it ready for rest and recovery.
Sympathetic vs Parasympathetic Nervous System Comparison Table
It is one of the most important differences and comparison articles in biology. The differences are listed below-
Feature | Sympathetic Nervous System (SNS) | Parasympathetic Nervous System (PNS) |
Origin | Thoracic and lumbar regions | Cranial and sacral regions |
Primary Function | Fight or flight response | Rest and digest the response |
Heart Rate | Increases | Decreases |
Pupils | Dilate | Constrict |
Airways | Expand | Constrict |
Digestion | Inhibits | Stimulates |
Energy Mobilisation | Increases (glucose release) | Promotes storage and absorption |
Sympathetic Nervous System (SNS)
The sympathetic nervous system prepares the body for 'fight or flight.' It increases vigilance and energy expenditure. This system also mobilises the body's resources during stress
Structure and Origin of SNS
Arises from the thoracic and lumbar regions of the spinal cord.
Composed of ganglia and neural paths extending to target organs.
Functions of SNS
Fight or flight response
Increased heart rate
Dilated pupils
Expanded airways
Inhibited digestion
Release of glucose from the liver for energy
Parasympathetic Nervous System (PNS)
The parasympathetic nervous system (PNS) does 'rest and digest' activities. It conserves energy and resources. It also facilitates restoration and upkeep functions.
Structure and Origin of PNS
Originate from the cranial and sacral regions of the spinal cord
It has long preganglionic and short postganglionic fibres
Ganglia are located near or inside the target organs
Functions of the PNS
Rest and digest the response
Decreased heart rate
Small pupils
Tightened airways
Stimulated digestion and glandular activity.
Promotes nutrient absorption and energy storage.
Role of Sympathetic and Parasympathetic Nervous System in Homeostasis
The Sympathetic Nervous System and Parasympathetic Nervous System work together to keep the body in balance. This balance is called homeostasis in the nervous system.
Dual innervation: Most organs receive input from both systems
Fine-tuned regulation depending on the body's needs
Heart: SNS increases heart rate, PNS decreases it
Digestive system: SNS inhibits digestion, and PNS stimulates it
Make sure the body acts appropriately based on the situation
Needed for adaptation to, as well as recovery from stress.
Fight or Flight vs Rest and Digest Response Explained
The Sympathetic Nervous System controls the fight or flight response. It prepares the body for stress. Heartbeat increases, blood pressure rises, and energy is released. Digestion slows down so the body can focus on survival.
The Parasympathetic Nervous System controls the rest and digest response. It calms the body after stress. Heartbeat slows, blood pressure decreases, and digestion is stimulated. Energy is stored, and recovery begins.
The difference between the sympathetic and parasympathetic nervous systems is clear. One excites the body for action, the other restores balance. Together, they maintain nervous system balance and ensure proper homeostasis in the nervous system.
Sympathetic vs Parasympathetic NEET MCQs
Q1. The function of our visceral organs is controlled by
Sympathetic and somatic neural system
Sympathetic and para sympathetic neural system
Central and somatic nervous system
None of the above
Correct answer: 2) Sympathetic and para sympathetic neural system
Explanation:
Option (a) is related to the peripheral nervous system and option (c) is not related to the regulation of visceral organs. But option (b) controls the functioning of visceral organs. The autonomic nervous system (option b) plays a crucial role in regulating involuntary functions such as heart rate, digestion, and respiratory rate. It is divided into the sympathetic and parasympathetic divisions, which work together to maintain homeostasis in the body.
Hence, the answer is option (2) Sympathetic and para-sympathetic neural system
Q2. Assertion: The sympathetic and parasympathetic nervous systems work in coordination with each other to maintain homeostasis in the body.
Reason: The two systems have opposite effects on target organs and systems, and their balance is critical for maintaining proper physiological function.
Both Assertion (A) and Reason (R) are the true and Reason (R) is a correct explanation of Assertion (A).
Both Assertion (A) and Reason (R) are the true but Reason (R) is not a correct explanation of Assertion (A).
Assertion (A) is true and Reason (R) is false.
Assertion (A) is false and Reason (R) is true.
Correct answer: 1) Both Assertion (A) and Reason (R) are the true and Reason (R) is a correct explanation of Assertion (A)
Explanation:
The assertion is correct in stating that the sympathetic and parasympathetic nervous systems work together to maintain homeostasis in the body. Homeostasis refers to the maintenance of a stable internal environment in the body, and the autonomic nervous system plays a crucial role in this process.
The reason is also correct in stating that the two systems have opposite effects on target organs and systems, and their balance is critical for maintaining proper physiological function. The sympathetic nervous system activates the "fight or flight" response, which prepares the body for stress or danger by increasing heart rate, dilating blood vessels, and releasing adrenaline, among other things. On the other hand, the parasympathetic nervous system activates the "rest and digest" response, which promotes relaxation and digestion by decreasing heart rate, constricting blood vessels, and stimulating digestion.
The balance between the two systems is crucial for maintaining homeostasis and proper physiological function. For example, an overactive sympathetic nervous system can lead to chronic stress, anxiety, and cardiovascular disease, while an overactive parasympathetic nervous system can lead to digestive issues and low blood pressure. Therefore, the assertion and reason are both correct and are interconnected. The two systems work together to maintain homeostasis in the body, and their balance is crucial for proper physiological function. The sympathetic and parasympathetic nervous systems have opposite effects on target organs and systems, and their balance is critical for maintaining homeostasis.
Hence, the correct answer is option 1) Both Assertion (A) and Reason (R) are the true and Reason (R) is a correct explanation of Assertion (A).
Q3. Assertion: Acetylcholine is the neurotransmitter found in the postganglionic nerve fibres of the parasympathetic nervous system, whereas adrenaline is found in the sympathetic nervous system.
Reason: Intestinal peristalsis is inhibited by the sympathetic nervous system while it is stimulated by the parasympathetic nervous system.
Both Assertion (A) and Reason (R) are the true and Reason (R) is a correct explanation of Assertion (A).
Both Assertion (A) and Reason (R) are the true but Reason (R) is not a correct explanation of Assertion (A).
Assertion (A) is true and Reason (R) is false.
Assertion (A) is false and Reason (R) is true.
Correct answer: 2) Both Assertion (A) and Reason (R) are the true but Reason (R) is not a correct explanation of Assertion (A).
Explanation:
The assertion is correct in stating that postganglionic nerve fibres of the parasympathetic nervous system release acetylcholine as the primary neurotransmitter, while the sympathetic nervous system releases adrenaline (also known as epinephrine) as the primary neurotransmitter.
The reason is also correct in stating that the sympathetic nervous system inhibits intestinal peristalsis while the parasympathetic nervous system stimulates peristalsis. The parasympathetic nervous system promotes digestion and activates the gastrointestinal tract, including peristalsis, which is the contraction of smooth muscles that move food along the digestive tract. On the other hand, the sympathetic nervous system inhibits digestive processes and is associated with the "fight or flight" response, which includes the redirection of blood flow away from the digestive system.
The release of different neurotransmitters by the two systems leads to different effects on the body. Acetylcholine released by the parasympathetic nervous system has a stimulatory effect, while adrenaline released by the sympathetic nervous system has an inhibitory effect on intestinal peristalsis.
In summary, the assertion and reason are both correct, but they are not interconnected. The parasympathetic nervous system releases acetylcholine and stimulates peristalsis, while the sympathetic nervous system releases adrenaline and inhibits peristalsis
Hence, the correct answer is option 2) Both Assertion (A) and Reason (R) are the true but Reason (R) is not a correct explanation of Assertion (A).
Recommended Video on the Sympathetic vs Parasympathetic Nervous System
Frequently Asked Questions (FAQs)
The Autonomic Nervous System (ANS) controls involuntary actions like heartbeat, breathing, and digestion. It has two divisions of the sympathetic and parasympathetic nervous systems.
The Sympathetic Nervous System prepares the body for fight or flight. It increases heart rate, blood pressure, and energy supply during stress.
The Parasympathetic Nervous System controls rest and digest. It slows the heartbeat, lowers blood pressure, and stimulates digestion for recovery.
The sympathetic system excites the body for action. The parasympathetic system calms the body for rest. Together, they maintain nervous system balance.
Both systems regulate organs through dual innervation. Example: the heart – sympathetic increases rate, parasympathetic decreases it. This ensures homeostasis in the nervous system.
