L9: PNS

Question 1

What are the two motor neurons of the peripheral nervous system?

Answer 1

Somatic and autonomic (visceral)

Question 2

How many motor neurons are involved in somatic and how many are involved in autonomic?

Answer 2

Somatic = 1 motor neuron
Autonomic = 2 motor neurons

Question 3

What is the effector in somatic motor and the effector in autonomic motor?

Answer 3

Somatic = skeletal muscle

Autonomic (visceral) = cardiac muscle, smooth muscle and glands

Question 4

What are the neurotransmitters in somatic and autonomic motor?

Answer 4

Somatic = Ach (acetylcholine)

Autonomic = Ach & norepinephrine

Question 5

Where are somatic and autonomic motor branches found? (The origin)

Answer 5

Somatic= anterior grey horn, nuclei of brain stem

Autonomic = lateral grey horn, nuclei of brain stem

Question 6

What are the two subdivisions of the autonomic nervous system?

Answer 6

Sympathetic and parasympathetic

Question 7

What do the sympathetic and parasympathetic nervous system have in common (similarities)

Answer 7

• intervate viscera
• organs have dual innervation ➡️ use both
• not on or off rather baseline firing of neurons increases or decreases

Question 8

What is the main function of the sympathetic and parasympathetic nervous system?

Answer 8

Sympathetic- fight or flight

Parasympathetic- rest and digest

Question 9

Origin of sympathetic and parasympathetic nervous system

Answer 9

Sympathetic- thoracolumbar

Parasympathetic- craniosacral

Question 10

What is the neuron length within the sympathetic and parasympathetic NS?

Answer 10

Sympathetic- short ➡️ long

Parasympathetic - long ➡️ short

Question 11

Where are the ganglia (collection of cell bodies) located in the sympathetic and parasympathetic NS?

Answer 11

Sympathetic- near spinal cord

Parasympathetic- near/ in effector

Question 12

Does the parasympathetic or the sympathetic NS cause mass activation?

Answer 12

Sympathetic

Question 13

What at is mass activation?

Answer 13

turns on entire response/ activation all at once

Question 14

What is divergence? Convergence?

Answer 14

Divergence = 1 spinal cord level ➡️ many ganglia

Convergence = many levels of spinal cord ➡️ 1 ganglion

Question 15

What’s the adrenal gland’s role in the ANS?

Answer 15

Sympathoadrenal system

• releases epinephrine from adrenal medulla ( adrenaline)

Question 16

What are the neurotransmitters in the ANS and where can they be found?

Answer 16

Ach, Epinephrine, Norepinephrine

Ach = pre ganglion in both sympathetic and parasympathetic

Norepinephrine = binds to effector in sympathetic

Question 17

What are the two types of cholinergic receptors? (Bind Ach)

Answer 17

Nicotinic and muscarinic

Question 18

Properties of a Nicotinic receptor

Answer 18

Excitatory ( na+ rushes in)
Ach receptor
Found on: post synaptic membrane of
- all autonomic ganglia
- all neuromuscular junctions

Question 19

Properties of muscarinic receptors

Answer 19

• binds epinephrine
• produces parasympathetic nerve effect in heart, smooth muscle & glands
• contain G proteins ( allowing 2 responses) ➡️ sympathetic do one thing and parasympathetic other

Question 20

Why is signal transduction necessary?

Answer 20

Many ligands are polar therefore they can’t enter the cell without help

Question 21

Signal transduction

Answer 21

Ligands bind to membrane bound receptors and initiates intracellular responses

Question 22

What are the adrenergic receptors?

Answer 22

Alpha adrenergic receptor
& beta adrenergic receptor

Question 23

Cholinergic muscarinic receptors are both inhibitory and excitatory- true or false

Answer 23

True

Question 24

Medulla oblongata

Answer 24

Control center for blood pressure: baroreceptor reflex