Difference Between Sympathetic & Parasympathetic Nervous System

The differences between sympathetic and parasympathetic nervous system according to their origin, character and effect on respective organs are listed in table.

Difference Between Sympathetic and Parasympathetic Nervous System

Sympathetic Parasympathetic
Origin From all thoracic and upper 3 lumbar segments. From cranial 3, 7, 9, 10 and sacral 2, 3, 4 segments.
Character Short preganglionic and long post-ganglionic fibres. Long preganglionic and short post-ganglionic (terminal ganglia).
Effect on Organs


1. H.R

2. Atrioventricular conduction

3. Atrial Refractory period

4. Atrial conduction

5. Ventricular conduction and contraction



1. Tachycardia

2. Increase

3. Decrease

4. Increase

5. Increase



1. Bradycardia

2. Decrease

3. Decrease

4. Increase

5. No effect

Smooth Muscles

1. Eye

2. Bronchi

3. GIT

4. Urinary bladder

5. Blood vessels


1. Mydriasis

2. Bronchodilatation (relaxation)

3. Relax wall and contact sphincters

4. Urine retention

5. Vasoconstriction and dilatation


1. Miosis and contraction of ciliary muscle

2. Bronchospasm (contraction)

3. Contract wall and relax sphincters

4. Micturition

5. Vasodilatation of some vessels


1. Salivary

2. Sweat


1. Thick viscid

2. Increase


1. Profuse watery

2. No effect

Sex Organs Ejaculation Erection
Read More Topics
Transmembrane enzyme linked receptors
G Protein coupled receptors
Factors affecting drug receptor interaction
Plasma protein binding of drug

About the author

Santhakumar Raja

Hi, This blog is dedicated to students to stay update in the education industry. Motivates students to become better readers and writers.

View all posts

Leave a Reply