FTM 72 - Anatomy of the Autonomic System Flashcards
What are the three target tissues of the ANS?
List the major functions of the SNS and PSNS
Which cranial nerves carry the SNS and PSNS efferents
PSNS Efferents
C3, C7, C9, C10, S2-S4
SNS Efferents
T1 - L2
Discuss the location of where the SNS and PSNS efferents synapse.
The SNS synapse in the cervical ganglion, the sympathetic chain near the vertebral column or the preaortic ganglia in the abdomen near the branches of the abdominal aorta.
The PSNS synapse at a parasympathetic gangli near the target organ
All sympathetic efferent pre-ganglionic neurons have their cell bodies in the _______ horn of the ___-___ vertebrae. the leave the spinal column through the ________ horn and then enter the sympathetic chain through the ______________. The post-ganglionic neurons will then exit the sympathetic chain via ______________.
Lateral
T1-L2
Ventral
White ramus communicans
Grey rami communicans
Where are GRCs and WRCs found?
White rami communicans are only found from T1-L2
Grey rami communicans are throughout the vertebral column
What are the different paths pre-ganglionic sympathetic efferents can take after entering the sympathetic chain?
What are the SNS targets in the body wall and limbs?
Which sympathetic efferent fibers synapse in the sympathetic chain at the same level they entered and then go on to innervate the body wall at that same level? What do the sympathetic efferents do that innervate above and below this region?
T1-L2
Above T1 efferents will ascend the sympathetic chain, synapse in the cervical ganglia and exit via GRCs to follow spinal nerves C1-C8
Below L2 efferents will descend the sympathetic chain synapse in lower lumbar and sacral chain ganglia and exit via GRCs to join spinal nerves L3-S5
What body regions do the SNS fibers from the spinal column above T1 innervate?
What body regions do the SNS fibers from the spinal column below L2 innervate?
Neck and upper limbs
Body wall below L2 and lower limbs
Describe the pathway of the SNS efferents that head to the cardiopulmonary plexus.
Their paths starts out enters the sympathetic chain just like any other SNS efferent, except these efferents are only at the T1-T4 level. From here they take one of two paths:
They can synapse at that level in the chain and leave medially as a cardiopulmonary nerve headed to the cardiopulmonary plexus
They can ascend in the chain and synapse in the cervical chain ganglia and leave medially as a cardioulmonary nerve headed to the cardiopulmonary plexus
Discuss the pathway of the SNS efferents headed to the abdominal and pelvic organs
Discuss the pathway of the PSNS spinal nerve efferents headed to targets in the head
What is so special about the vagus nerve?
It is the only PSNS cranial nerve functioning in the cervical, thoracic and lumbar regions. It brings PSNS preganglionics to the thoracic and GI viscera, up to the left colic flexure
Discuss the importance of the sacral PSNS efferents.
Describe the pathway of the PSNS sacral efferents.
Describe the origin and path of the visceral afferents
What do the visceral afferents travelling with the PSNS fibers and SNS fibers detect?
