Sympathetic Nervous System

Quick Answer: The sympathetic nervous system model is an anatomy teaching model of the sympathetic division of the autonomic nervous system, showing the chain of ganglia beside the spinal column and the nerves that run from it to the organs. Physiology, nursing and biology students use it to follow the pathways behind the fight-or-flight response.

The Sympathetic Division on a Model

The autonomic nervous system runs the organs without conscious effort and has two main divisions. The sympathetic division prepares the body for action: it speeds up the heart, widens the airways and pupils, raises blood glucose and slows digestion. Its partner, the parasympathetic division, works mainly through the vagus and other cranial nerves and through the sacral part of the spinal cord, and it tends to restore the resting state.

Sympathetic outflow leaves the spinal cord only from the thoracic and upper lumbar segments, roughly T1 to L2, which is why it is called the thoracolumbar outflow. Preganglionic fibres pass to the sympathetic trunk, a paired chain of ganglia lying on either side of the vertebral bodies from the neck down to the coccyx. Some fibres synapse in the chain; others pass straight through to prevertebral ganglia such as the coeliac ganglion in front of the aorta, and the adrenal medulla is supplied by preganglionic fibres directly. On a sympathetic nervous system model students can trace these routes from cord to chain to organ.

How this particular model is built is not given in its title: it could be a relief on a board, a figure with the chain laid beside a spine, or another layout, and neither size nor material is listed. If you need particular organs or the parasympathetic side shown too, ask for the layout before ordering.

Teaching Uses

• Contrasting sympathetic and parasympathetic effects on the heart, lungs, eye, gut and bladder
• Explaining the fight-or-flight response and the release of adrenaline by the adrenal medulla
• Tracing preganglionic and postganglionic neurons in first-year physiology and nursing pharmacology
• Showing why damage to the cervical sympathetic chain gives a drooping eyelid and a small pupil on one side (Horner syndrome)

Specifications

Care & Handling

• Dust the sympathetic nervous system model with a soft brush; thin nerve strands and small ganglia are the parts most easily chipped.
• Keep it out of direct sunlight so the colour coding of nerves, ganglia and organs does not fade.
• Carry it with both hands, supporting the base or board rather than any projecting part.

Why Choose LabEquip

Physiology departments, nursing schools and senior biology labs usually want this autonomic model to sit beside a whole-body nerve model. LabEquip lists it among its biology lab products, next to the human nervous system model that covers the brain, spinal cord and limb nerves. Ask about the layout and quantities through the contact page.

Frequently Asked Questions

What is the difference between the sympathetic and parasympathetic systems?

Both are divisions of the autonomic nervous system. The sympathetic division prepares the body for stress or exercise, raising heart rate and diverting blood to the muscles. The parasympathetic division favours rest and digestion, slowing the heart and increasing gut activity. Most organs receive both.

Why is the sympathetic system called thoracolumbar?

Its preganglionic neurons lie in the lateral horn of the spinal cord in the thoracic and upper lumbar segments, about T1 to L2. The parasympathetic system is called craniosacral because its outflow comes from the brainstem and the sacral cord.

What is the sympathetic trunk?

It is a paired chain of ganglia joined by nerve fibres, running along each side of the vertebral column from the base of the skull to the coccyx. Fibres from the spinal cord enter it through white rami, and fibres returning to the spinal nerves leave through grey rami.

Which neurotransmitters does the sympathetic system use?

Preganglionic neurons release acetylcholine at the ganglion. Most postganglionic neurons release noradrenaline at the target organ, with sweat glands a notable exception that use acetylcholine. The adrenal medulla adds adrenaline to the blood.

How is the adrenal medulla linked to the sympathetic system?

The adrenal medulla behaves like a modified sympathetic ganglion. It receives preganglionic fibres directly and, when stimulated, releases adrenaline and some noradrenaline into the bloodstream, spreading the fight-or-flight effect around the body.

Who uses a model of the sympathetic nervous system?

It is mainly used in senior secondary biology and in nursing, pharmacy and physiology courses, where students must learn the autonomic pathways before studying drugs that act on them, such as beta blockers and bronchodilators.

Last Updated: September 2026