Anatomy Lecture 6_ANS

Question 1

At what level do sympathetic nerves exit the spine

Answer 1

T1-L2, the thoracolumbar

Question 2

At what level do parasympathetic nerves exit

Answer 2

CN III, VII, IX, X (the vegus nerve)

S2-S4

Question 3

What are the 4 fates for sympathetic nerves

Answer 3

1) synaps in the sympathetic ganglion then exit through the gray ramus and join a spinal nerve
2) travel up or down the sympathetic chain to synaps then exit the gray ramus and join a spinal nerve
3) Synaps in the sympathetic ganglion then go directly to the heart or lungs as a splachnic nerve
4) Pass through the trunk and head directly as splanchic nerves to innervate viseral organs

Question 4

What is refered pain

Answer 4

It is when sinals from viseral afferent nevers get picked up by somatic afferent nerves and the brain preceives the viseral pain in the body wall (ie raidiating pain in the left arm during a MI

Question 5

How many nurons are involved in sympathetic signaling and where are their cell bodies located

Answer 5

It is a two cell system. The presynaptic cell body is located in the intermediolateral cell column in the CNS. The postsynaptic cell body is located in a sympathetic ganglion in the PNS

Question 6

What path do sympathetic nerves exit the CNS

Answer 6

ventral root (same root that somatic efferents exit)