Autonomic Nervous System

Question 1

How many neurons are involved in an autonomic nervous system impulse?

Answer 1

2

Preganglionic and postganglionic

Question 2

In the sympathetic nervous system, which is longer: the preganglionic or postganglionic fiber?

Answer 2

Postganglionic fibers are longer

Remember they synapse in the sympathetic chain which is right next to the spinal cord

Question 3

How many neurons go to the adrenal medulla?

Answer 3

Just one. There’s no ganglion in between the CNS and the adrenal medulla

Question 4

Where do parasympathetic fibers originate in the spinal cord?

Answer 4

Craniosacral regions

Question 5

Where in the CNS do the sympathetic fibers originate?

Answer 5

Thoracolumbar region

Question 6

Which neurotransmitter do Preganglionic sympathetic fibers spit out?

Answer 6

Acetylcholine

ALL Preganglionic fibers in the ANS spit out ACh

Question 7

The adrenal medulla acts like a ganglion. What “neurotransmitter” does it release?

Answer 7

Epinephrine is released as a hormone into the blood

Also secretes norepinephrine but 80% of it is epinephrine

Question 8

In an extreme emergency, what does the adrenal gland do?

Answer 8

Releases epinephrine (80%) and norepinephrine (20%) into the bloodstream for a body-wide “adrenaline rush”

Question 9

What type of receptor is used by postganglionic parasympathetic neurons?

Answer 9

Muscarinic

Question 10

What type of receptors are used by postganglionic sympathetic neurons? (Except for sweat glands)

Answer 10

a1 a2 B1 B2

Question 11

What type of receptor is in all ganglia as well as the adrenal medulla that acts like a ganglion?

Answer 11

Nicotinic (N2)

Different type though than the nicotinic receptors in somatic nervous system

Question 12

What type of receptor is used by Postganglionic sympathetic nerurons innervating the sweat glands?

Answer 12

Muscarinic

they bind ACh, which is secreted by the postganglionic sympathetic fiber….only time it’s not epi, norepinephrine

Question 13

What type of receptor is on the adrenal medulla?

Answer 13

Nicotinic (N2)

Question 14

Can muscarinic receptors respond to epinephrine?

Answer 14

No, they only respond to ACh

Question 15

What must happen first for norepineprhine to be degraded?

Answer 15

Must be reuptaked into the presynaptic neuron

Question 16

What are MAO and COMT

Answer 16

The enzymes that degrade norepinephrine after its reuptaked into the presynaptic neuron

Question 17

What is the backbone for dopamine, norepinephrine and epinephrine?

Answer 17

Tyrosine

Question 18

After norepinephrine is released into the cleft what happens to it?

Answer 18

Some of it diffuses away, and some of it is reuptaken into the presynaptic neuron by a norepinephrine reuptake transmitter

Question 19

What type of receptors are on ganglia?

Answer 19

N2

Question 20

What is meant by reciprocal effects?

Answer 20

It means that for organs that have sympathetic and parasympathetic innervation, each effect is usually opposite. Allows for FINE CONTROL of organ function.**

(Gas pedal and brake pedal)

Question 21

What is meant by “Cooperative Effects” for an organ that has dual innervation?

Answer 21

It means they promote the same goal

Question 22

What are some examples of duality innervated organs that have cooperative effects

Answer 22

Salivary glands
Lacrimal glands
Male sexual response

Question 23

What is the effect of sympathetic and parasympathetic influence on the salivary glands?

Answer 23

Sympathetic: viscous saliva secretion

Parasympathetic: watery saliva secretion

Question 24

What type of innervation:
Hair follicles
Brown adipose
Adrenal Medulla
Kidneys
Most arterioles and veins (except penis and heart circulation)

Answer 24

Sympathetic adrenergic ONLY

Question 25

What is the only organ that receives sympathetic cholinergic innervation?

Answer 25

Sweat glands

Question 26

What are the only blood vessels that are dually innervated?

Answer 26

Penis coronary circulation

Question 27

Are arteries and capillaries innervated at all?

Answer 27

NO

Question 28

What are the only blood vessels that can change diameter?

Answer 28

Arterioles and veins

Question 29

What would the sympathetic innervation do to insulin release>

Answer 29

It would inhibit it, we wouldnt’ want to be storing glucose at this time because we need it!

Question 30

Which division is more predominant when the bladder is filling?

Answer 30

Sympathetic (Detrussor is relaxed Internal sphincter is constricted)

Question 31

Which division is more predominant when bladder is emptying?

Answer 31

Parasympathetic Detrussor is contracted, Internal sphincter is relaxed

Question 32

What is tonic activity?

Answer 32

Activity of an organ under “resting” conditions. Determined by the ratio of parasympathetic and sympathetic stimulation acting on it at the same time

Question 33

If you block the muscarinic receptors, what kind of a response will you have?

Answer 33

A sympathetic response overall

Question 34

If you block the adrenergic receptors, what type of response will you have?

Answer 34

Parasympathetic

Question 35

Why does your dog pee when it’s excited or scared?

Answer 35

It’s an autonomic reflex that is not integrated by the CNS. Even though it’s normally under control, the reflex can’t be overcome. Autonomic reflexes are often urination and defecation

Question 36

What part of the brain is the main intergrator of the ANS

Answer 36

Hypothalamus

Question 37

If you take a drug that is an antagonist of muscarinic receptors (ex: atropine, scopolamine), what kind of effects will you have?

Answer 37

Mydriasis, tachycardia, difficulty voiding urine, etc. Sympathetic nervous system will predominate so you will get fight-or-flight effects. (Muscarinic receptors are in Parasympathetic post ganglionic and sympathetic post ganglionic for sweat glands)