LP #103 ANS

Question 1

• more complex than parasympathetic division
• innervates large number of structures, including extremities, sweat glands, etc.
• nerve fibres arise from T12-L2 spinal levels
• a.k.a thoracolumbar division
• sympathetic ganglia located superior & inferior to spinal levels (T1-L2)

Answer 1

Sympathetic division

Question 2

• a.k.a paravertebral ganglia
• lie in vertical row on either side of vertebral column
• extend from base of skull to coccyx
• chain of 23 ganglia:
• 3 cervical
• 11 thoracic
• 4 lumbar
• 4 sacral
• 1 coccygeal
• postganglionic nurons mostly innervate organs superior to diaphragm

Answer 2

Sympathetic trunk (chain) ganglia

Question 3

Primary paravertebral ganglia are:

Answer 3

• superior cervical
• middle cervical
• inferior cervical

Question 4

• anterior to vertebral column
• post-ganglionic neurons primarily innervate structures inferior to diaphragm
• primary prevertebral ganglia:
• celiac ganglia
• superior mesenteric ganglia
• inferior mesenteric ganglia
• these ganglia serve abdomiopelvic ganglia

Answer 4

Prevertebral ganglia

Question 5

Celiac ganglion a.k.a solar ganglion. This ganglion is part of ______ _____ (a collection of ganglia), also called the _____ ______

Answer 5

• celiac plexus

- solar plexus

Question 6

Sympathetic Innervation: SC segments

T1-T5 & T5-T9

Answer 6

• T1-T5:
• head, neck, arms, heart, lung
• synapse w/in cervical ganglia
• T5-T9:
• form greater splanchnic nerve
• innervates liver, stomach, spleen, kidney, adrenal glands
• synapse w/in celiac ganglion

Question 7

Sympathetic Innervation: SC segments

T9-T12 & L1-L2

Answer 7

• T9-T12
• form lesser splanchnic nerve
• innervates small intestine, proximal 1/2 of large intestine
• synapses w/in superior mesenteric ganglion
• L1-L2
• forms lumbar & sacral splanchnic nerves
• innervates pelvic viscera
• synapse w/in inferior & hypogastric ganglia

Question 8

• contains sympathetic preganglionic fibres
• post-ganglionic fibers (axons) are unmyelinated (grey)
• pre-ganglionic fibers are myelinated (white)

Answer 8

Rami communicantes (singular)

Question 9

*when synapses are made in chain ganglia, post-ganglion if axons (unmyelinated) enter rami of adjoining spiral nerves via communicating branches called ?

Answer 9

Grey rami communicantes

Question 10

*preganglionic axons (myelinated) travelling to sympathetic trunks carry myelinated fibres, forming?

Answer 10

White rami communicantes

Question 11

• parasympathetic fibers never travel within spinal nerves

- rami communicantes are associated only with ?

Answer 11

Sympathetic division