ANS BS

Question 1

parasympathetic NTs

Answer 1

ACh, NE, E

Question 2

Sympathetic NTs

Answer 2

ACh

Question 3

Parasympathetic gen overview

Answer 3

Origins: craniosacral (brain S1-S4)

Fibres: long preganglionic, short postganglionic (synapse at diest from spinal cord)

Location of ganglia: in visceral effector organs

Question 4

Sympathetic div gen overview

Answer 4

origin: thoracolumbar (T1-L2)
Lengh of fibres: short preganglionic, long postganglionic (synapse close to spinal cord)
location of ganglia: close to spinal cord

Question 5

sympathetic division

• where preganglionic nerons
• make what spinoal cord stuc

Answer 5

preganglionic neurons in T1 to L2

sympathetic neurons produce the spinal cord lateral horms

Question 6

where do sympathetic division preganglionic fibres pass through

Answer 6

white rami communicantes to enter the sympathetic trunk (paravertebral trunk)

Question 7

how many sympathetic trunk ganglia

Answer 7

23 sympathetic trunk ganglia in the sympathtic trunk

-

Question 8

Upon entering a sympathetic trunk ganglion, a preganglionic fiber may do 1 of 3 things:

Answer 8

1) Synapse at the same level
2) Synapse at a higher or lower level
3) Synapse in a distant collateral ganglion anterior to vertebral column

Question 9

SNS path to head

• emerge
• synapse

Answer 9

emerge from T1 - T4
synapse in superior cervicle ganglion

These fibers:

• Innervate skin & blood vessels of head
• Stimulate dilator muscles of iris
• Inhibit nasal & salivary glands

Question 10

SNS to thorax

Answer 10

Preganglionic emerge T1-T6
synapse in cervicle trunk ganglia

postganglionic fibres emerge from ganglia and enter C4 to C8 to innervate
+heart (cardiac plexus) lungs (pulmonary plexus)
-thyroid gland
-skin (majority)

Question 11

`

Answer 11

Preganglionic fibers from T5 to L2 travel through splanchnic nerves to synapse in prevertebral (collateral) ganglia

Contributes to plexus

Question 12

SNS to abdomen: ciliac ganglion

Answer 12

liver gall bladder stomach spleeen pancreas proximal duodenum

Question 13

SNS to abdomen: superior mesenteric ganglion

Answer 13

ancreas, distal duodenum, jejunum, ileum, ascending colon + transverse colon

Question 14

SNS to abdomen: inferior mesenteric ganglion

Answer 14

descending colon, sigmoid colon + upper rectum

Question 15

SNS to pelvis

Answer 15

pathways synapse in sympathetic trunk ganglia

Sacral splanchnic nerves innervate genitalia and bladder

Question 16

SNS pathway to adrenal medulla

Answer 16

Preganglionic fibers pass directly to adrenal medulla without synapsing in celiac ganglion

STIM: adrenal medulla secretes NE and E to blood
+more E than NE secretion

Question 17

cholinergic fibres

• what release
• where in SNS pathways

Answer 17

1) release ACh
2) Sympathetic preganglionic axons
+ parasympathetic preganglionic and postganglionic axons
(somatic motor neurons)

Question 18

Adrenergic fibres

1) what release
2) what fibres in SNS pathways

Answer 18

1) release NE OR E
2) most sympathetic postganglionic axons
* Exceptions: sympathetic postganglionic fibers secrete ACh at sweat glands & some blood vessels in skeletal muscles

Question 19

Cholinergic receptors

1) how named
2) what are the two types

Answer 19

1) named after the drugs that act on them mimicking ACh

2) Nicotinic (binds nicotine) and muscorinic (binds shroom toxin)

Question 20

nicotinic receptors

Answer 20

all ganglionic neurons SNS and PSNS
motor endplates of SKM cells
hormone producing cells in adrenal medulla

EFFECT OF ACh ALWAYS STIMULATORY AT NICOTINIC RECEPTORS

Question 21

muscarinic receptors

Answer 21

all effector cells stimulated by postganglionic cholinergic fibres

*Effect of ACh at muscarinic receptors can be either inhibitory or excitatory

Question 22

Adrenergic receptors

1) types
2) effect
3) NE and E interations with types

Answer 22

1) alpha - typically stimulatory
beta - typically inhibitory (except heart)
2) effect depends on receptor subclass of target organ
3) NE stims alpha more than beta
E stims beta and alpha equally

Question 23

Alpha one receptor type (adrenergic)

Answer 23

more important that alpha 2

• smooth muscle contraction (constricts BVs)
• gland secretion

Question 24

alpha 2 receptor type (adrenergic)

Answer 24

reduces cAMP levels and nhibits the cell

Question 25

Beta 1 receptor (adrenergic)

Answer 25

heart

Question 26

beta 2 receptor (adrenergic)

Answer 26

lungs

Question 27

beta 3 receptor type (adrenergic)

Answer 27

frees E from fats

Question 28

dual innervation

Answer 28

most organs have SNS and PSNS innervation | -allows for dynamic antagonism - allows for percise control of visceral activity

Question 29

Parasympathetic tone

Answer 29

dominates heart and smooth muscle of digestive and urinary tracts +slows heart +dictates normal activity levels of digestive and urinary tract SNS can ovveride in times of stress

Question 30

sympathetic tone AKA vasomotor tone

Answer 30

keeps blood vessels in continual state of partial constriction

Question 31

Unique functions of sympathtic NS

Answer 31

``` ONLY SYMPATHETIC INNERVATION -sweat glands and errector pilli - thermoregulatory responses Kidneys - release of renin most BVs - BP Adrenal medulla - metabolic effects ```

Question 32

localized vs diffuse effects

Answer 32

PSNS - short lived highly localized control over effectors | SNS - long lasting body wide effects, fast

Question 33

why is SNS effects long lasting

Answer 33

NE inactivated more slowly than ACh | NE and E are released into blood and stay there until destroyed by liver

Question 34

short vs long reflexes

Answer 34

short reflexes do not go through CNS (skip to post ganglionic fibres) long reflexes go through CNS (use preganglionic fibres exiting CNS)

Question 35

visceral reflexes SNS

Answer 35

cardioacceleratory reflex vasomotor reflexes pupillary reflex ejaculation in males

Question 36

commmunication in ANS

Answer 36

cerebral cortex (frontal lobes) = limbic system (emotional input) = hypothalamus (overall integration of ANS) = brainstem (Regulation of pupil size, respiration, heart, blood pressure, swallowing) = spinal cord (urination, defecation, erection, ejaculation reflexes)

Question 37

visceral reflex arc

Answer 37

1) sensory receptor in viscera 2)) visceral sensory neuron 3) integration center +could be preganglionic neuron +could be dorsal horn interneuron +could be in walls of GI tract 4) Efferent pathway (2-neruon chain) +preganglionic neuron - postganglionic neuron 5) visceral effector