Unit 4 Lecture 33

Question 1

Weird fact about the parasympathetic preganglionic neuron

Answer 1

it’s longer than the sympathetic pregang. neuron

Question 2

What are the 4 main cranial nerves?

Answer 2

• III Oculomotor
• VII Facial
• IX Glossopharyngeal
• X Vagus

Question 3

What is important about all of the cranial nerves?

Answer 3

They are all “mixed cranial nerves”

Question 4

Function of Oculomotor (III)

Answer 4

moves eyeball and stimulates tear ducts (lacrimation)

Question 5

Function of Facial (VII)

Answer 5

salivation

Question 6

Function of glossopharyngeal (IX)

Answer 6

swallowing and salivation

Question 7

Function of Vagus (X)

Answer 7

*carries 80% of parasympathetic outflow to heart, airways, liver, gallbladder, stomach, small intestine and part of large intestine

Question 8

Cranial portion of the parasympathetic ns

Answer 8

1. Pregang. nerurons found in pons or medulla
2. info carried by cranial nerves III, VII, IX, X
3. 80% of PSNS info carried by Vagus X

Question 9

Sacral portion of the PSNS

Answer 9

pregang. neurons in sacral region (S2-S4) and exit in pelvic nerve

Question 10

What 4 ganglia do cranial pregang. neurons synapse at?

Answer 10

Ciliary, pterygopalatine, submandibular, otic

CPSO

Question 11

Define cholinergic receptors

Answer 11

respond to acetylcholine (ACh)

Question 12

What are the two types of cholinergic receptors?

Answer 12

1. Nicotinic receptors

2. Muscarinic receptors

Question 13

Define nicotinic receptors

Answer 13

found on sympathetic and parasympathetic cell bodies and dendrites of postgang. neurons (w/in ganglion)

• can only generate excitatory post-synaptic potentials (EPSP)

Question 14

Define muscarinic receptors

Answer 14

found on membrane of target tissues innervated by parasympathetic postgang. axons

• can generate both EPSP and inhibitory post-synaptic potentials (IPSP)

Question 15

Goal of the parasympathetic ns

Answer 15

Salivation, crying (lacrimation), urination, defecation

Question 16

What are specific responses to PSNS

Answer 16

• increased digestive enzyme/hormone secretion
• increased smooth muscle activity of the GI tract
• Constriction of pupils for near vision
• Decreased heart rate, contractility, blood pressure
• Contraction of muscular wall of bladder and intestine -> urination and defecation
• increased secretion of the lacrimal glands

Question 17

Define syncope

Answer 17

fainting = vasovagal reaction

• lose consciousness bc lack of O2
• avoid by laying down in supine position, elevating feet, contracting leg and arm muscles to increase blood to brain