Neuroscience Quiz & Exam 2

Front 1

Type ? motor neurons innervate the muscle fibers

Back 1

Type A Motor Neurons

Front 2

Type ? motor neurons innervate the intrafusal muscle fibers of the muscle spindles

Back 2

Type B Gamma Motor Neurons

Front 3

Intrafusal Muscle Fibers detect?
They are innervated by?

Back 3

the amount and rate of change of length in a muscle; they are proprioceptors; innervated by type B gamma motor neurons

Front 4

extrafusal muscle fibers are innervated by? and do what?

Back 4

alpha motor neurons and they contract to generate skeletal movement

Front 5

Difference between A and C motor fibers

Back 5

A fibers are myelinated and have 4 subdivisions. C fibers are not myelinated

Front 6

Renshaw cells are a type of ?

Back 6

interneuron

Front 7

Function of Renshaw cells?

Back 7

they are cells in the SC that inhibit motor ff around them to allow for specific/fine mvmts; allow for appropriate reflex and motor responses

Front 8

Muscle ? monitor the absolute length and change in length of of a muscle

Back 8

Spindles

Front 9

? tell about the change in tension and absolute tension of a muscle

Back 9

Golgi Tendon Organs

Front 10

? structures help to maintain proper mm tone

Back 10

GTOs

Front 11

what part of the muscle has no contractile components?

Back 11

the central portion of the muscle spindle

Front 12

where are the contractile parts of the muscle spindle?

Back 12

in the intrafusal fibers located at the ends of the muscle spindle

Front 13

T or F - the entire muscle spindle acts as a receptor bc its ends are contractile

Back 13

true

Front 14

the central part of the muscle spindle is innervated by what ? These convey what type of info?

Back 14

1A and 2 sensory motor neurons; info concerning the change in length of the central pt of the m spindle

Front 15

the sensory information provided by the 2 types of intrafusal muscle fibers enable one to tell ?

Back 15

the position of their muscle and the rate at which it is changing

Front 16

when there is a slow change in muscle length, what fibers are activated in the muscle spindle?

Back 16

both the primary (1A) and secondary (2) fibers are activated.

Front 17

a slow change in muscle length activates 1A and 2 sensory motor neurons of the muscle spindle. this is referred to as a ? response

Back 17

static response (lasts several minutes or as long as the muscle is stretched

Front 18

a sudden change in muscle length will activate ? type of muscle fibers in a ? response

Back 18

only the 1A (primary) sensory fibers activated in a "dynamic response" which lasts only a few seconds

Front 19

the sensitivity of the muscle spindle can be changed by activation of ?

Back 19

either the alpha or gamma motor inputs (afferent fibers)

Front 20

the alpha motor neurons are controlled at the ? and ? level

Back 20

the SC and Cortical (the outer layer of the cerebruml) levels

Front 21

Gamma afferents are controlled at what levels?

Back 21

cerebellum, basil ganglia and the cortex (cortical level)

Front 22

alpha and gamma motor neurons change the sensitivity of the muscle spindle based on ?

Back 22

the tone of the muscle that is needed

Front 23

1A sensory fibers innervate which part of the muscle spindle?

Back 23

the nuclear bag fiber

Front 24

type 2 sensory fibers innervate which part of the muscle spindle

Back 24

the nuclear chain fiber

Front 25

alpha and gamma motor neurons are afferent or efferent?

Back 25

efferent

Front 26

Gamma motor neurons are located in the ?

Back 26

brainstem and spinal cord

Front 27

Alpha motor neurons are located where ? and are responsible for ?

Back 27

In the SC; controlling skeletal muscle

Front 28

? motoneurons regulate the gain of the stretch reflex by adjusting the level of tension in the intrafusal muscle fibers of the muscle spindle. This mechanism sets the baseline level of activity in ?motoneurons and helps to regulate muscle length and tone

Back 28

Gamma, Alpha

Front 29

a type of intrafusal muscle fiber that lies in the center of a muscle spindle. Each has a large number of nuclei concentrated in bags and they cause excitation of both the primary and secondary nerve fibers.

Back 29

nuclear bag fiber

Front 30

Their ? are aligned in a chain and they excite the secondary nerve. They are static while the ? fibers are dynamic in comparison.

Back 30

nuclear chain fiber; nuclear bag fibers

Front 31

motor neurons are located in what part of the SC

Back 31

anterior horn

Front 32

motor neurons are located in what part of the SC

Back 32

anterior horn

Front 33

sensory neurons are located in what part of the SC

Back 33

dorsal horn

Front 34

sensory neurons are located in what part of the SC

Back 34

dorsal horn

Front 35

what happens when muscle spindle control is lost?

Back 35

lose the ability to maintain a steady/still position bc there is a loss of proprioception

Front 36

what happens when muscle spindle control is lost?

Back 36

lose the ability to maintain a steady/still position bc there is a loss of proprioception

Front 37

? elicit dynamic and static responses to changes in muscle tension

Back 37

GTOs

Front 38

? elicit dynamic and static responses to changes in muscle tension

Back 38

GTOs

Front 39

? reflex moves you away from the point of stimulus

Back 39

flexor reflex

Front 40

? reflex moves you away from the point of stimulus

Back 40

flexor reflex

Front 41

? reflexes opens up the limb

Back 41

extensor reflex

Front 42

4 kinds of walking reflex

Back 42

stepping reflex, reciprocal stepping of opposite limbs, diagonal stepping of the 4 limbs, galloping reflex

Front 43

? reflex is where you get inhibition and excitation of antagonist muscle groups

Back 43

stepping/walking reflex

Front 44

? reflex is where one side moves forward and then the opposite side forward

Back 44

reciprocal stepping of opposite limbs

Front 45

? reflex is where one front limb goes forward while the opposite back limb goes forward too

Back 45

diagonal stepping of the four limbs

Front 46

? reflex is when the 2 front legs go back while the 2 back legs come forward

Back 46

galloping reflex

Front 47

excitation of agonists and inhibition of antagonists is what type of reflex

Back 47

crossed extensor reflex

Front 48

? controls all the body's visceral functions

Back 48

ANS

Front 49

ANS initiated responses/changes are slow or rapid?

Back 49

rapid

Front 50

the ANS is activated by ?

Back 50

SC, brain stem, hypothal and cerebral cortex centers as well as by visceral reflexes

Front 51

"?" functions are controlled by the ANS - these are the funx that keep you alive

Back 51

vegitative functions

Front 52

ANS consists of

Back 52

SNS, PNS and ENS

Front 53

SNS nerves originate from what spinal levels?

Back 53

T1-L2

Front 54

SNS preganglionic neuron cell bodies reside where?

Back 54

SC and brain stem

Front 55

preganglionic neurons of the SNS project to

Back 55

the paravertebral sympathetic chains parallel to the SC

Front 56

SNS has short or long pregang fibers?

Back 56

short

Front 57

SNS postganglionic neuron cell bodies reside where?

Back 57

in the SNS chains ganglia

Front 58

some postganglionic fibers of the SNS go back to the SC and along skeletal nerves to where ?

Back 58

sweat glands, piloerector muscles and blood vessels

Front 59

most postganglionic neurons of the SNS from the sympathetic chain or prevertebral ganglia project to where?

Back 59

directly into target organs

Front 60

special pregang neurons of the SNS project along the ? to the adrenal medulla

Back 60

splanchnic nerve

Front 61

Sympathetic Nerve Fibers from T1 level go to the ?

Back 61

Head

Front 62

Sympathetic Nerve Fibers from T2 level go to the ?

Back 62

neck

Front 63

Sympathetic Nerve Fibers from 3-61 level go to the ?

Back 63

thorax

Front 64

Sympathetic Nerve Fibers from T7-11 level go to the ?

Back 64

abdomen

Front 65

Sympathetic Nerve Fibers from T12, L1-2 level go to the ?

Back 65

legs

Front 66

How many descending pathways are in the pathways in the white matter of the SC

Back 66

7

Front 67

What are the 2 corticospinal tracts

Back 67

lateral corticospinal tract and anterior corticospinal tract

Front 68

functions of the lateral corticospinal tract

Back 68

fine motor funx and regulation of sensory

Front 69

functions of the anterior corticospinal tract

Back 69

gross and postural motor funx

Front 70

what are the 2 vestibulospinal tracts?

Back 70

lateral vestibulospinal tract and medial vestibulospinal tract

Front 71

function of the vestibulospinal tracts

Back 71

postural reflexes

Front 72

function of the rubrospinal tract

Back 72

motor funx

Front 73

funxs of the reticulospinal tract

Back 73

regulation of sensory transmission (especially pain) and regulation of spinal reflexes

Front 74

function of the autonomic descending tract

Back 74

regulation of autonomic funxs

Front 75

funx of the tectospinal tract

Back 75

head turning reflex

Front 76

funx of the medial longitudinal fascicuclus

Back 76

coordination of head and eye mvmts

Front 77

what are the 7 descending pathways in the white matter of the SC

Back 77

cortiocospinal, vestibulospinal, rubrospinal, reticulospinal, autonomic-descending, tectospinal, medial longitudinal fasciculus

Front 78

3 main sensory systems

Back 78

pain-temp, proprioception, light touch

Front 79

what are the 2 sensory tracts for pain and temperature

Back 79

spinothalamic and spinoreticular tracts

Front 80

where are the spinothalamic and spinoreticular tracts located in the SC?

Back 80

anterior horn

Front 81

describe pathway of spinothalamic and spinoreticular tracts for pain and temp sensations

Back 81

enter cord, crosses to the opposite 1/2 w/in 1 or 2 cord segments then ascends to the thalamus on the opposite side and synapses. spinothalamic moves to the cerebral cortex after synapsing in the thalamus. spinoreticular tract does NOT reach the thalamus

Front 82

lesion of the spinothalamic tract will result in?

Back 82

contralateral loss of pain and temp below the level of the lesion

Front 83

aka for the posterolateral fasciculus

Back 83

lissauer's tract

Front 84

axons enter the SC at the ? and send short ascendg and descendg ff longitudinally in ? tract

Back 84

dorsal root zone, lissauer's tract (fasciculus)

Front 85

2 component of the posterior column

Back 85

nucleus gracilis, nucleus cunneatus

Front 86

? transmits impulses originating from receptors in muscles, tendons, ligs, jt caps and skin assoc'd w/ dermatomes T6 to Co1

Back 86

fasciculus gracilis

Front 87

fasciculus gracilis is associated with dermatomes ? to ?

Back 87

T6 to Co1

Front 88

? is located lateral to the fasciculus gracilis and transmits impulses originating from receptors in mm, tendons, ligs, jt caps and skin assoc'd w/ dermatomes C2 to T1

Back 88

fasciculus cunneatus

Front 89

fasciculus cunneatus is assoc'd w/ dermatomes ? to ?

Back 89

C2 to T1

Front 90

synaptic areas for proproiception, sterogenesis and vibration

Back 90

nucleus gracilis and cunneatus

Front 91

pathway for proprioception, stereogenesis and vibratory sensation

Back 91

stays on the ipsi side of the SC after entering, crosses over at the junx of the SC and brain stem, travels to cerebral cortex

Front 92

lesion in the posterior columns result in ?

Back 92

decrease in the proprioception, stereogenesis (mostly) and vibratory sensation on the ipsi side of the SC below the level of the lesion

Front 93

posterior column crosses over at the ?

Back 93

medial leminscus

Front 94

leminscus =

Back 94

junction of brain stem and sc

Front 95

this tract is for unconscious proprioception and does not cross over

Back 95

spinocerebellar tract

Front 96

3 main connections b/w the cerebellum and brain stem

Back 96

superior, middle and inferior cerebellar peduncles which connect the midbrain, pons and medulla

Front 97

the superior, middle and inferior cerebellar peduncles connect which parts of the brain ?

Back 97

midbrain, pons and medulla

Front 98

light touch involves a combination of ? tracts

Back 98

spinothalamic, fascisculus graciclis and fascisculus cunneatus path patterns

Front 99

why is light touch sensation not easily lost?

Back 99

bc it crosses over the SC at lower levels and remains partly uncrossed until it reaches the brain stem

Front 100

why is the light touch sensation the least effected by lesions?

Back 100

bc the dorsal column and spinothalamic columns also carry light touch sensations

Front 101

this tract carries touch sensation via the VPL (ventral posterolateral nucleus) of the thalamus

Back 101

spinocervicothalamic tract

Front 102

pain and temp, proprioception and light touch sensory pathways all cross over and in the ?, (except for the ? pathway) and from there go to the ?

Back 102

thalamus, (except for the unconscious proprioception pathway), cerebral cortex

Front 103

a lesion in the sensory pathways of the ? may result in a contralateral defecit

Back 103

cerebral cortex

Front 104

PNS fibers leave the CNS via ? nerves

Back 104

CN 3, 7, 9, 10 and SN 1-4

Front 105

75% of all PNS ff are in what nerve?

Back 105

CN 10 - vagus

Front 106

preganglionic ff of the PNS project to?

Back 106

directly to target organs

Front 107

postganglionic cell bodies of the PNS are where?

Back 107

in the target organs

Front 108

vagus nerve supplies which organs

Back 108

heart, lungs, esoph, ST, SI, GB, Pancreas, ureter and colon

Front 109

3rd cranial nerve supplies ?

Back 109

papillary sphincters and cilliary mm

Front 110

7th cranial n supplies

Back 110

lacrimal, submandibular and nasal glands

Front 111

9th CN supplies

Back 111

parotid gland

Front 112

sacral nn supply

Back 112

lower colon, rectum, bladder, lower ureters and ext'l genitalia

Front 113

which part of the ANS funx independently

Back 113

ENS

Front 114

sensory neurons of the ENS monitor ?

Back 114

GI tension, chemicals and hormone levels in blood

Front 115

interneuronal circuits of the PNS control ?

Back 115

GI mm, motility, blood flow, mucus and enzymes

Front 116

? plexus of the ENS is composed of linear chains of neurons located bw longitudinal and circular layers

Back 116

myenteric plexus

Front 117

myenteric plexus is located b/w which layers?

Back 117

longitudinal and circular layers

Front 118

myenteric plexus controls?

Back 118

GI mm tone, contractions intensity, frequency and velocity

Front 119

? plexus of the ENS is composed of nonlinear neurons scattered in the submucosa

Back 119

submucosal plexus

Front 120

submucosal plexus controls

Back 120

intestinal secretions and absorption

Front 121

ENS funx can be modified by

Back 121

SNS, PNS, hypothalamus and solitary nucleus in the medulla

Front 122

ach secreting neurons are called ?

Back 122

cholinergic

Front 123

epi and norepi secreting neurons are called

Back 123

adrenergic

Front 124

neurotransmitters synth is in the

Back 124

terminal endings of the nerve fibers

Front 125

enz that catalyzes acetyl co a and choline into ach

Back 125

acetyl tranferase

Front 126

ach binds to ? and ? receptors

Back 126

muscarinic and nicotinic

Front 127

ach is hydrolyzed by

Back 127

acetylcholinesterase

Front 128

tyrosine --> (enz?) --> DOPA --> (enz?) --> dopamine --> (enz?) --> norepinephrine

Back 128

tyrosine hydroxylase, dopa decarboxylase, dopamine b hydroxylase

Front 129

20% of secretion from adrenal medulla = ? and 80% = ?

Back 129

20% norepi, 80% epi

Front 130

norepi is methylated by ? --> epinephrine

Back 130

PNMT (phenylethanolamine-n-methyltransferase)

Front 131

epi and norepi secretions reach areas ?

Back 131

not innervated by the SNS and last 5-10 times longer than SNS

Front 132

norepi binds to ? receptors

Back 132

alpha and beta

Front 133

norepi is removed from synapses by

Back 133

active reuptake, diffusion into blood or split by MAO &/or catecholomethyltransferase enzymes

Front 134

all preganglionic neurons are ?

Back 134

cholinergic

Front 135

all postgang neurons of PNS are ?

Back 135

cholingergic

Front 136

SNS ff to sweat glands and piloerector mm are ?

Back 136

cholinergic

Front 137

type of SNS receptors

Back 137

cholinergic, adrenergic

Front 138

SNS is inhibitory to

Back 138

GI tract funx, erection, nasal, lacrimal and salivary secretions

Front 139

SNS beta receptors cause ?, alpha receptors cause ?

Back 139

vasodilation, vasoconstriction

Front 140

? is caused by the activation of the hypothalamus by fear or severe pain (SNS)

Back 140

mass discharge

Front 141

mass discharge results in

Back 141

increased mental activity, blood pressure and flow to all active mm; inhibits GI and KD funx

Front 142

isolated discharge of the SNS is responsible for ?

Back 142

heat regulation, vasodilaiton in the coronary and cerebral bld vsls and (inhibition of ? - not sure if this is correct) GI and local reflexes

Front 143

? effects are highly specific and do not have mass discharge

Back 143

PNS

Front 144

? reflex controls blood pressure

Back 144

baroreceptor reflex

Front 145

GI reflexes control ?

Back 145

secretions, motility and defecation

Front 146

bladder reflex is responsible for ?

Back 146

micturition

Front 147

erection is by ? and ejaculation by ?

Back 147

PNS, SNS

Front 148

vascular tone is set by ?

Back 148

SNS

Front 149

GI tone is set by

Back 149

PNS

Front 150

denervation causes?

Back 150

loss of tone with intrinsic compensation and supersensitivity of affected organ to neurotransmitters

Front 151

types of ANS induced disorders

Back 151

GI, cardiovascular and sexual disorders

Front 152

? drugs have the same effects as activation of the SNS

Back 152

sympathomimitic drugs

Front 153

? inhibit the SNS in one way or another

Back 153

antagonists - ie, alpha and beta blockers

Front 154

pyrostigmie is a ? drug

Back 154

parasympathomimitic - has same effect as activation of PNS

Front 155

examples of drug antagonists of PNS

Back 155

curare (nicotinic) and muscarinis (atropine) blockers

Front 156

inactive norepi + alpha 1 receptor --> ? and activates ?

Back 156

GDP, phospholipase C

Front 157

active norepi + alpha 1 receptor --> ?, activates ? which leads to ?

Back 157

GTP, phospholipase C, DAG and IP3 which leads to increased intracellular calcium

Front 158

IP3 activation by phospholipase C and PIP3 causes Ca2+ to be released from

Back 158

ER or SR

Front 159

inactive norepi + beta receptor -->

Back 159

GDP and adenyl cyclase

Front 160

active norepi + beta receptor -->

Back 160

GTP, adenyl cyclase activation --> cAMP