Somatic Autonomic Motor Flashcards
1
Q
Major anatomical components of NS:
A
- CNS
- PNS
2
Q
CNS is made of:
A
- spinal cord
- brain
3
Q
PNS is made of:
A
- all nerves that enter and exit from CNS
- 12 pairs of cranial nerves
- 31 pairs of spinal nerves
4
Q
3 major physiological divisions of NS:
A
- sensory
- integrative
- motor
5
Q
Sensory division:
A
handles input portions of PNS and CNS
6
Q
Sensory division detects:
A
environmental changes (internal and external)
7
Q
Components that make up sensory division:
A
- sensory organs
- thalamus
- sensory cortices
8
Q
Integrative division:
A
- CNS
- processes and stores sensory info
9
Q
Motor division:
A
handles output from CNS and PNS
10
Q
Motor division generates…
A
movements and glandular secretions
11
Q
Components that make up the motor division:
A
- brainstem
- cerebellum
- motor cortex
- basal ganglia
12
Q
PNS is made up of…
A
bundles of nerve fibers (ganglia)
13
Q
Paired spinal nerves in PNS attach to ____ by ____
A
spinal cord by roots
14
Q
Types of roots:
A
- dorsal
- ventral
15
Q
Dorsal root is where…
A
sensory axons enter CNS
- also has dorsal root ganglion
16
Q
Dorsal root ganglion:
A
enlargement containing primary sensory nerve cell bodies
17
Q
Ventral root is where…
A
motor axons exit CNS
18
Q
PNS have _____ nerve fibers that are…
A
myelinated, insulated by Schwann cells
19
Q
PNS is divided into two portions:
A
- somatic
- autonomic
20
Q
Somatic motor division:
A
- somatic sensory nerves from somatosensory organs
- somatic motor nerves that go to skeletal muscles
21
Q
Somatosensory organs have…
A
sensory receptors in body surfaces (skin, skeletal muscle, joints)
22
Q
Somatic motor unit is made up of…
A
alpha motor neuron and all myofibers (skeletal muscle cells) it innervates
23
Q
Somatic motor unit is under _______ control
A
voluntary (conscious)
24
Q
Somatic motor units:
A
- cholinergic transmission: release ACh at axon terminals
- nicotinic receptors coupled w/ Na+ ion channel
- no antagonistic innervation
25
Autonomic motor division is made of...
- visceral sensory nerves (from organs)
- visceral motor nerves (to organs)
- visceral reflexes
26
Visceral sensory nerves have diffuse...
distribution of receptors
27
Somatic motor nuclei are found in the...
ventral horn
28
Visceral sensory nerves have peripheral nerves that enter the...
dorsal horn
29
Autonomic efferent nuclei are found in the...
lateral horn
30
Visceral pain often shares...
input pathways w/ somatic division
- aka referred pain
- part of visceral sensory nerves
31
Visceral motor nerves go to organs such as...
- smooth muscle
- cardiac muscle
- glands
32
Visceral motor nerves are under...
involuntary (unconscious) control
33
Visceral motor nerves have a ______ motor unit
autonomic
- 2 motor neurons (pre and post ganglionic neurons)
- ganglion
- effector tissue
34
Visceral reflexes can be mediated at the level of...
- autonomic ganglion
- spinal cord
- brain stem
- hypothalamus
35
Two subdivisions of ANS motor neurons:
- sympathetic NS (SNS)
| - parasympathetic NS (ParaSNS)
36
Sympathetic NS have effectors that...
prepare body for stress responses
37
Parasympathetic NS have effectors that...
help maintain homeostasis of daily routines
38
Neurons that leave the ANS have a connecting synapse at a...
ganglion before reaching the target organ
39
Neuron leaving the CNS is the...
preganglionic neuron
40
Cell body of preganglionic neuron is located in...
intermediolateral gray of spinal cord (aka lateral horn)
41
Preganglionic neuron leaves by...
ventral root
42
Axons in the preganglionic neuron are made of...
type A beta fibers
43
T/F: preganglionic neurons are cholinergic
T, they release ACh at axon terminals
44
Preganglionic neurons synapse at...
autonomic ganglion w/ postganglionic neuron in PNS
45
Autonomic ganglion is the place where...
the synapse occurs between postganglionic and preganglionic neuron
- gray matter outside the CNS
46
Autonomic ganglion has...
- axonal ends of preganglionic neuron
- dendrites and cell bodies of postganglionic neuron
- some interneurons
- support cells
47
Postganglionic neuron leaves the...
ganglion and travels to effector organs
48
Postganglionic neuron has a receptive membrane that has receptors for...
ACh
49
Postganglionic neuron are primarily _____ receptors
nicotinic
| - coupled to LGC Na+
50
Axons of postganglionic neuron are made of...
type C fibers
51
Neurotransmitters released at axon terminals at postganglionic neurons depend on...
which division was activated
52
The two major divisions of ANS differ according to...
- origin
- location of ganglia
- neurotransmitter release
- distribution and action on effector tissue
53
SNS has ____ nerves that originate in the _____
efferent, thoracolumbar origins (T1-L2)
54
SNS is strongly activated during...
emergency/stress situations
| - prepares for "fight or flight"
55
Ganglia of the SNS is located...
very closely to spinal cord
56
SNS has _____ preganglionic neurons and _____ postganglionic neurons
short, long
57
The SNS has short preganglionic neurons b/c of...
the location of ganglia
58
Postganglionic neurons in SNS are...
adrenergic
| - releases 80% norepi and 20% epi
59
Axon terminals of postganglionic in SNS are...
modified to series of bulbous enlargements (varicosities)
60
Neurotransmitters from postganglionic neurons in the SNS are...
diffusely released
61
Axon terminals of postganglionic in the in SNS contain _____ receptors
alpha 2 (autoreceptors)
62
Axon terminal pumps in the postganglionic neurons of SNS are...
very active and reuptake 50-80% of intact neurotransmitters
63
Effector tissue for SNS:
- smooth muscle
- cardiac muscle
- glands
64
Effector tissue for SNS contains...
alpha and beta receptors
65
Effector tissue for SNS act via...
G-protein mediated effects
66
Norepi prefers...
alpha receptors
67
Epi prefers...
beta receptors
68
Response of effector tissues in the SNS depends on...
- # and type of receptors
| - coupling mechanism of effector cells
69
Adrenal medulla:
large SNS ganglia
70
Adrenal medulla provides...
longer duration of action by release of epi into blood
71
Adrenal medulla makes ____ epi and ____ norepi
80%, 20%
72
Actions of epi in SNS:
- cardiostimulation
- weak vasoconstriction
- metabolic effects
73
ParaSNS has efferent nerves that originate from...
craniosacral origins
- cranial nerves 3, 5, 9 and 10
- sacral segments S1-S4
74
75% of the efferent nerves in the paraSNS are supplied by...
the vagus nerve (cranial nerve 10)
| - supplies viscera of thorax and abdomen
75
Ganglia for paraSNS are located in...
wall or organ being supplied
76
ParaSNS have ____ preganglionic neurons
long b/c of distal location of ganglia
77
ParaSNS have _____ postganglionic neurons
short cholinergic
| - releases ACh at axon terminals
78
Effector tissues of paraSNS:
- smooth muscle
- cardiac muscle
- glands
- same as SNS
79
Effector tissues of paraSNS contains ____ receptors
muscarinic
80
Effector tissues of paraSNS act via...
G-protein mediated effects
81
Effector tissues of paraSNS will have _______ responses due to ______
short lasting, high tissue levels of acetlycholinesterase
82
Effector tissues of paraSNS are in organs w/...
dual innervation
83
Effector tissues of paraSNS generally _____ effects of SNS
counteracts
84
Drugs that affect ANS can act at...
- SNS or paraSNS ganglia
- postganglionic neuronal endings
- effector tissue
