Peripheral Nerves and the Autonomic Nervous System

Question 1

Draw an overview of Neural input to and output from the the CNS?

Answer 1

Slide 2 PPT

Question 2

What are the two nerve pathways for viceral afferents?

Answer 2

Vagus and Spinal

Question 3

What is the pathway for somatic afferents?

Answer 3

Spinal

Question 4

What are the three afferent receptors/neurons and some examples?

Answer 4

Nociceptors- pain (stabbed)
Mechanoreceptors- pressure and stretch (stretching of lungs)
Proprioceptors- changes in muscle tendon length/tension (reflex, hitting knee)

Question 5

What does the golgi tendon apparatus do?

Answer 5

protects tendons by shutting off muscle spindle proprioceptors when stretched too far

Question 6

What is a motor unit?

Answer 6

the motor neuron and all the skeletal muscle fibers it innervates

Question 7

What type of receptors and neurotransmitters are in muscle fibers?

Answer 7

Nicotinic and Acetylcholine

Question 8

What are the mechanisms to alter skeletal muscle contraction via the NM junction?

Answer 8

1- Tetrodotoxin- blocks neuronal Na+ channel
2- Conotoxin- blocks Ca2+ channel
3- Curarine- blocks the nicotinic receptor
4- Acetylcholine- opens nicotinic receptor
5- Nicotine- opens nicotinic receptor
6- Physostigmine- inhibits acetylcholinesterase
7- Botulinum(botox)- blocks Ach release

Question 9

Where do the efferent autonomic nerves originate from?

Answer 9

Medulla (the headless chicken)

Question 10

What happens to the HR when we inhale and exhale?

Answer 10

inhale- HR increases

exhale- HR decreases

Question 11

What happens to parasympathetic output when we inhale and exhale?

Answer 11

inhale- decreases PS output

exhale- increases PS output

Question 12

What are the differences between the the sympathetic and parasympathetic nerve pathways (where they exit the CNS and synapse)?

Answer 12

Sympathetic- exit from entire spine, synapse at preganglion chain
Parasympathetic- exit from the medulla and sarcral, synapse throughout the body (especially the gut)

Question 13

What does the adrenal medulla release and what stimulates it?

Answer 13

epinephrine

sympathetic preganglionic neurons stimulate it

Question 14

What is the target organ for somatic nerves?

Answer 14

Skeletal muscle

Question 15

What neurotransmitters do you think of with alpha and beta receptors?

Answer 15

Norepinephrine and epinephrine

Question 16

What organs have alpha and beta adrenergic receptors (3)?

Answer 16

smooth muscle, cardiac muscle, and glands

Question 17

What are the agonists and antagonists for the nicotinic Ach receptor?

Answer 17

Agonist: Ach, nicotine
Antagonist: Curare (rocuronium)

Question 18

What are the agonists and antagonists for the muscarinic Ach receptor?

Answer 18

Agonist: Ach, muscarine
Antagonist: Atropine, Glycopyrrholate