Lect 4 Autonomic Nervous System

Question 1

2 subdivisions of ANS

Answer 1

Parasympathetic

Sympathetic

Question 2

Sympathetic

Answer 2

mobilizes body for action in stressful and dangerous situations
fight or flight

Question 3

Parasympathetic

Answer 3

regulates the body’s functions to conserve energy

rest and digest

Question 4

Activation of sympathetic nervous system causes

Answer 4

pupil dilation
increase heart rate
decrease gut motility
blood diverted from gut to skeletal muscle
viscous saliva

Question 5

activation of the parasympathetic nervous system

Answer 5

pupil constriction
decrease heart rate
increase gut motility 
decreased blood to skeletal muscle 
watery saliva

Question 6

Similarities between sympathetic and parasympathetic

Answer 6

both have a 2 neuron chain
Cell body of 1st neuron is in CNS (myelinated)
Cell body of second is in the PNS (not myelinated)

Question 7

ganglion

Answer 7

collection of cell bodies in the PNS

Question 8

Cell bodies of PNS parasympathetic preganglionic nuerons reside in

Answer 8

brainstem nuclei

sacracl spinal cord

Question 9

cell bodies of para preganglionic neurons in brainstem nuclei

Answer 9

CN 3, 7, 9, 10

the brainstem nuclei innervate structures in the head, thorax and abdomen

Question 10

cell bodies of para preganglionic neurons in sacral spinal cord

Answer 10

sacral spinal cord innervate structures in the pelvis

Question 11

parasympathetic postganglionic cell bodies reside

Answer 11

in ganglia close to target organ or within the wall of the target organ (heart, lung, stomach, bladder)
shorter PostGG leads to more specific targeting

Question 12

Cell bodies of preganglionic sympathetic neurons

Answer 12

reside in Spinal cord levels (T1-L3)

specifically, preganglionic neuron resides in the intermediolateral cell column (lateral horn)

Question 13

course of sympathetic preganglionic fiber 3 options

Answer 13

leaves the spinal cord via the anterior horn of the spinal cord and do on of following:
1. synapse in the sympathetic chain at the same level

2. Ascend or descend in the sympathetic chain prior to synapsing at another level
3. pass through the sympathetic chain without synsapsing and travel to prevertebral ganglia via a collection of fibers called splanchnic nerves

Question 14

Sympathetic chain

Answer 14

located bilaterally along the length of the spinal column

formed by ganglia along its length, these cell bodies are location of postganglionic sympathetic neuronal cell bodies

Question 15

Sympathetic preganglionic course synapse at same level

Answer 15

pre synapses at sympathetic chain in same level (myelinated) and 2nd order neuron (unmyelinated) passes into periphery

Question 16

Prevertebral ganglia

Answer 16

celiac ganglion
superior mesenteric ganglion
inferior mesenteric ganglion

located in the abdomen, anterior to the vertebral bodies and abdominal aorta

comprised of sympathetic ganglion cells (cell body of postganglionic symp fibers)

Question 17

postganglionic sympathetic fiber cell bodies

Answer 17

reside in sympathetic chain/trunk or prevertebral ganglia

Question 18

sympathetic vs parasympathetic & extremities

Answer 18

symp fibers travel to peripheral nerves and pass to extremities and body wall
para fibers do not pass to the extremities or body wall