Quiz #1: ANS (10)

Question 1

What are the functional classes of neurons?

Answer 1

1. afferent neurons
2. interneuron
3. efferent neuron

Question 2

Skeletal muscles are innervated by what type of neurons?

Answer 2

motor neurons

Question 2

What are the parts that make up the autonomic nervous system?

Answer 2

1. sympathetic
2. parasympathetic
3. enteric

Question 3

What is the organization of the ANS?

Answer 3

Pathway of 2 neurons (pre/postganglionic) and 2 synapses
Ganglion: cluster of neuronal cell bodies outside of CNS (where you can find the second neuron of ANS)

Question 4

Where is the cell body of the preganglionic neuron found?

Answer 4

CNS (brain/spinal cord)

Question 5

Where is the cell body of the postganglionic neuron found?

Answer 5

autonomic ganglia

Question 6

What is collateral ganglia?

Answer 6

aka prevertebral ganglia
when the preganglionic fiber does NOT synapse to the postganglionic fiber in the sympathetic chain
instead form synapse in the collateral ganglia
innervate viscera (INTERNAL ORGANS)

Question 7

What is the sympathetic nervous system?

Answer 7

• preganglionic fibers original from lateral horn of the T1-L2 spinal cord (SHORT)
• postganglionic fiber found in sympathetic ganglia chain/trunk (LONG)
• exceptions: some sympathetic ganglionic neurons found in prevertebral ganglia

Question 8

What is the pathway involving the first synapse (between pre/postganglionic fiber)?

Answer 8

1. Action potential comes down presynaptic fiber to terminal
2. open calcium channel for depolarization
3. triggers release of ACh (NT)
4. goes to cleft and binds to ACh receptors on postsynaptic cell

Question 9

What is ChAT and what does it do?

Answer 9

choline acetyltransferase
synthesis of ACh
choline + acetyl CoA = ACh

Question 10

What is the pathway involving the second synapse (between postganglionic fiber/effector organ)?

Answer 10

1. Action potential comes down postsynaptic fiber to terminal
2. open calcium channel for depolarization
3. triggers release of NE (NT)
4. NE bind to receptors on effector organs OR diffuse into blood OR exogenous uptake (not through receptors) OR reuptake

Question 10

Where is ACh synthesized?

Answer 10

At presynaptic cell terminal

Question 10

What is the sympathetic preganglionic neurotransmitter?

Answer 10

Acetylcholine (ACh)

Question 11

What is AChE and what does it do?

Answer 11

Acetylcholinesterase
breaks down ACh to choline +acetic acid

Question 12

What is the sympathetic postganglionic neurotransmitter?

Answer 12

Norepinephrine (NE) or Noradrenaline

Question 13

Where is NE synthesized?

Answer 13

At presynaptic postganglionic cell terminal

Question 13

What is dopamine?

Answer 13

intermediate product in production of norepinephrine
Tyr –> dopamine –> NE

Question 14

What is the role of tyrosine in the postganglionic fiber?

Answer 14

Precursor to NE
starting material
Tyr –> dopamine –> NE

Question 15

What is epinephrine?

Answer 15

Adrenaline
NOT a NT in the ANS

Question 16

What is epinephrine derived from?

Answer 16

Norepinephrine (NE)

Question 17

The adrenal medulla can be classified as a(n) ____________ organ, as it gets innervated to release epinephrine.

Answer 17

effector

Question 17

Where is epinephrine synthesized for the ANS?

Answer 17

Adrenal medulla of the adrenal gland
NOT from the postganglionic neuron terminal

Question 18

Where is epinephrine synthesized for the CNS?

Answer 18

neuron terminal

Question 19

Where is epinephrine released?

Answer 19

into the blood
that is how it gets to the target organ receptors

Question 20

What are adrenergic receptors?

Answer 20

receptors for adrenaline (epinephrine/NE) ALL are G-protein coupled receptors

Question 20

What is adrenergic receptor α1?

Answer 20

most popular type of adrenergic receptor α1 effector is most sympathetic target tissue + most arteries greater affinity for NE than E activates IP2-Ca2+ pathway EXCITATORY

Question 21

What is adrenergic receptor α2?

Answer 21

greater affinity for NE than E effector is digestive organs inhibit cAMP Ex. control gastric acid INHIBITORY

Question 22

What is adrenergic receptor β1?

Answer 22

for the heart equal affinity for NE/E activate cAMP EXCITATORY

Question 23

What is adrenergic receptor β2?

Answer 23

for the smooth muscle of arterioles and bronchioles activate cAMP INHIBITORY

Question 24

When the sympathetic NS is activated, what is the effect on the artery/arterioles respectively? Why are the effects similar/different?

Answer 24

artery: - receptor type: α1 - vasoconstriction - blood pressure increase arterioles: - receptor type: β2 - vasodilation - blood pressure decrease ** different bc different receptors **

Question 24

Sympathetic activation is also known as ________________.

Answer 24

Fight and Flight/Fright exercise, heart failure, hemorrhage, pain, emotional stress or excitement, etc

Question 25

What is mydriasis?

Answer 25

Dilation of the pupils in response to fight and flight response

Question 26

What are the receptors for the sweat gland?

Answer 26

cholinergic receptors exception to sympathetic chain synapse

Question 27

Where does the preganglionic parasympathetic NS originate from?

Answer 27

cranial nerve in brain (CN III, VII, IX, X) and sacral regions (S2, S3, S4) of spinal cord LONG

Question 28

Where are the postganglionic parasympathetic NS located in?

Answer 28

Terminal ganglia SHORT

Question 29

What are the cranial nerves we need to know?

Answer 29

CN III (3) CN VII (7) CN IX (9) CN X (10) - Vagus nerve

Question 30

What is the parasympathetic preganglionic neurotransmitter?

Answer 30

Acetylcholine (ACh) same as postganglionic

Question 31

What is the parasympathetic postganglionic neurotransmitter?

Answer 31

Acetylcholine (ACh) same as preganglionic

Question 32

What are the type of receptors for the parasympathetic system?

Answer 32

1. nicotinic 2. muscarinic

Question 33

What are muscarinic receptors?

Answer 33

activated by ACh EXCITATORY OR INHIBITORY autonomic postganglionic fibers effector: cardiac muscle, smooth muscle, and glands mechanism: activates many G-protein coupled receptor pathways usually mediates Na+/K+ influx for depolarization/hyperpolarization --> excitation/inhibition

Question 33

Another name for the parasymapthetic system is _____________.

Answer 33

rest and digest

Question 34

What are nicotinic receptors?

Answer 34

activated by ACh or nicotine EXCITATORY autonomic preganglionic fibers effector: all autonomic postganglionic cell bodies/adrenal medulla mechanism: opens nonspecific cation receptor-channels usually mediates Na+/K+ influx for depolarization --> excitation

Question 35

What is miosis?

Answer 35

pupil constriction during parasympathetic activation

Question 36

What is the dual innervation of sympathetic and parasympathetic nervous system?

Answer 36

when innervated by both sympathetic/parasympathetic for MOST visceral organs

Question 36

Which visceral organs are sympathetic only?

Answer 36

kidney adrenal glands sweat glands blood vessels

Question 37

What is the enteric nervous system innervated by?

Answer 37

Myenteric plexus (Auerbach's) Submucosal plexus (Meissner's)

Question 37

What is the enteric NS?

Answer 37

Sensory information from digestive organs brain in the gut

Question 37

What is an agonist?

Answer 37

Something that mimics neurotransmitter response

Question 38

What is an antagonist?

Answer 38

Blocks the neurotransmitter response

Question 39

TRUE OR FALSE The enteric system function independently of the CNS

Answer 39

TRUE

Question 40

What is the ANS regulated by?

Answer 40

1. Medulla - center for control - cardiovascular - respiratory - digestive 2. Hypothalamus - integrating ANS - somatic/endocrine system to achieve homeostasis 3. Cortex - emotion - personality - learning