Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Semester 2 > Pathophys Block 3 > Flashcards

Pathophys Block 3 Flashcards

1
Q

Skeletal Muscle Structure

A

Muscle –> Fasciculus –> Muscle fibers –> fiber -> myofibril

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Cell membrane of muscle

A

Sarcolemma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Stem cells for muscle growth

A

satellite cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is a myofiber made up of?

A

many myofibrils (parallel)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Myofibers are ___nucleated

A

multi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Each nuclei of myofibers maintains a certain area of local control within the cell, called___

A

Myonuclear domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Satellite (stem cells) are ____ until activated

A

quiescent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

neuronal circuits for walking & reflexes are contained within the ____

A

spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Basis of muscle hypertrophy

A

Satellite cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Higher brain center activate and command ___

A

neuronal circuits (walking, maintaining equilibrium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Motor neurons are located in the ___ portion of the spinal cord

A

anterior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Motor neurons are ___ than other neurons

A

bigger (50-100%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Sensory fibers enter cord and are transmitted to higher centers, or ____

A

synapse locally to elicit motor reflexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Somatic motor neuron types

A

Alpha (various), Beta & Gamma (muscle spindles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Targets of special visceral motor neurons

A

mostly facial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Targets of general visceral motor neurons

A

mostly cardiac and smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where the alpha motor neuron innervates fiber (other fibers in motor unit)

A

neuromuscular junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Network of tubules that conduct signal within the muscle fiber

A

Sarcoplasmic reticulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What powers activity of the muscle fibers

A

mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does the number of mitochondria in the muscle fiber depend on

A

fiber type and training status

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

thick filament

A

myosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

thin filament

A

actin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

attached to Z line

A

actin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which motor neurons original in the spinal cord

A

lower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

lower motor neurons (spinal cord) directly or indirectly do what?

A

innervate effector targets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What motor neurons originate in the motor cortex (precentral gyrus)

A

upper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What fibers make up the bulk of muscle?

A

Extrafusal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What fibers provide the force for muscle contraction?

A

Extrafusal fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are extrafusal fibers stimulated by?

A

alpha motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Intrafusal fibers are encapsulated in sheaths to form ____

A

muscle spindles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Gamma motor neuron stimulation excites what fibers

A

intrafusal fibers (in muscle spindle)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Where are upper MNs located

A

motor cortex (prefrontal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Where are lower MNs located

A

brainstem and SC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are symptoms in upper MN lesions

A

spasticity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are symptoms in lower MN lesions

A

paralsis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

NT for upper MNs

A

glutamate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

NT for lower MN

A

ach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

where do upper MN target

A

within the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what fibers provide pathways for multi-segmental reflexes

A

propriospinal fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Muscular Dystrophy sx

A

Weakness (esp. pelvic girdle muscles), marked lordosis, enlarged calves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Muscular Dystrophy genetics

A

X-linked (more common in men)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What are propriospinal fibers important for

A

proprioception (sensing of relative position of body parts and strength of effort used in movement)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Most signals from brain terminate on ____

A

interneurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Characteristics of interneurons

A

small and highly excitable; compromise neuronal circuitry for motor reflexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

where do you have secondary clefts

A

motor end plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Muscarinic receptor location

A

smooth and cardiac muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Nicotinic receptor location

A

skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Nicotinic receptors are ____ channels

A

ligand-gated ion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Muscarinic receptors are ____ channels

A

2nd messenger signaling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

In MG, immune system attacks receptors at____

A

NMJ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Ach binding sites are blocked by ____

A

curare, various toxins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Where is the muscle spindle located

A

muscle belly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

The muscle spindle senses ___

A

muscle length & (rate of change in length)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Where is the golgi tendon organ located

A

tendon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

The golgi tendon organ senses

A

tendon tension (and rate of change)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What ion reestablishes membrane potential in AP

A

K+ (out)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is the muscle AP mainly driven by

A

influx of Na+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What are voltage gated Na+ channels responsible for

A

rapid influx of sodium ions during the AP potential of nerve cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What channels can we change to change AP

A

K+ (Na+ not as much variation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

difference in fiber types and fiber contractions are based on ____

A

what sodium channels are present and what potassium channels are present (mainly K)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

signals from muscle sensory receptors are mainly for ____ muscle control

A

intrinsic (subconscious)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Muscle spindles detect both static and dynamic changes in ____

A

muscle length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Na/K pump

A

3 Na out, 2 K in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What can cause inhibition of Na/L pump and cause cell to swell and burst

A

ouabain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What carries the nervous impulses inside the cell

A

Transverse tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Where are Ca ion released from

A

sarcoplasmic reticulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What effect does tropomyosin have

A

allow myosin heads to attach to actin filaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Larger muscles with coarse movements have ___ muscle spindles

A

few

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What pump collects Ca after AP to get ready to go again

A

SERCA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Basic walking reflexes reside in ___

A

spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Pressure on the bottom of the feet causes ____

A

extensor reflex (more complex)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Inflammation of peritoneum can cause __

A

abdominal muscle spasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Pain signals can cause ___

A

reflex activation and spasm of local muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

ATP causes what in terms of muscle contraction

A

reseting cross bridge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

contraction and relaxation time series response to a single stimulus

A

twitch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

size is relative to ____ in a twitch

A

intensity of stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

fully summated response -fused into maximal curve

A

tetanus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Twitch responses add to each other when multiple stimuli do not allow full relaxation

A

summation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

faster you use muscle affects its

A

strength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

less frequency, _____ force

A

less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

at long lengths, ____ ability to develop force

A

low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

faster you go, ____ force

A

less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

what can muscle cramps be due to

A

cold, ischemia, over-activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

reflex contraction ____ painful stimulus and causes _____ muscle contraction

A

increases; more

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

crossed extensor reflex stimulus

A

pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

crossed extensor reflex response

A

ipsilateral flexion; contralateral extension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

painful stimulus causes limb to withdraw from stimulus

A

flexor withdrawal reflexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

crossed extensor reflex

A

painful stimulus elicits an extensor reflex in opposite limb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

crossed extensor reflex afferent fibers

A

II, III, IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

crossed extensor reflex number of synapses

A

polysynaptic reflex arc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

what do muscle spindles and GTOs transmitted to higher centers informing the brain of

A

changes in muscle tension and length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

golgi tendon organ response

A

relaxation of muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

golgi tendon organ stimulus

A

muscle contraction (tension)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

golgi tendon organ afferent fibers

A

Type IB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

GTO number of synapses

A

disynatpic reflex arc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

what is the function of the GTO

A

equalize force among muscle fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

GTO signal muscle force where?

A

throughout the entire physiological range

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

what does coactivation of alpha and gamma motor neurons cause

A

prevents spindle from being unloaded during contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

what is the stretch reflex response

A

contraction of muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

what is the stretch reflex stimulus

A

muscle stretch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

what is the stretch reflex # of synapses

A

monosynaptic reflex arc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

what is the stretch reflex afferent fibers type

A

Type Ia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

what does the static response respond to

A

degree of stretch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

what does the dynamic response respond to

A

rate of change of length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

intrafusal fibers are innervated by____

A

gamma MNs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

nuclear bag intrafusal fibers are innervated by____

A

Type Ia sensory afferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

nuclear chain intrafusal fibers are innervated by____

A

Type II sensory afferents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

nuclear bag intrafusal fibers

A

dynamic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

nuclear chain intrafusal fibers

A

static

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

What is muscle aging a result of

A

Decreased muscle fibers, muscle fiber number, and muscle length

111
Q

What is increased in aging muscle

A

number of fiber with central nuclei & ragged red fibers

112
Q

ragged red fibers show what

A

breakdown of mitochondria

113
Q

Muscle function in aging

A

Decreased relative strength, Decreased power (decreased Vmax myosin)

114
Q

What is greater, the decrease in strength or power in aging muscles?

A

power

115
Q

Muscle power is important to what?

A

ADLs, fall risk, etc.

116
Q

Motoneuron changes in aging

A

decreased number of motor neurons, decreased diameter of motor neurons, increased size but decreased complexity of motor endplate

117
Q

Aging - axons and NMJs

A

increased size but decreased complexity of motor end plate

118
Q

Aging - motor unit changes

A

decreased MU firing rate and increased MU size

119
Q

What muscles are impacted more by aging

A

lower body; distal

120
Q

Mechanisms of muscle action

A

Primary vs secondary; changes in physical activity; denervation/reinervation process’ oxidative/nitrosative stress/ DNA damage

121
Q

Human disuse models

A

Spinal cord injury, immobilization, unloading, detraining

122
Q

What are disuse effects on fiber types dependent on

A

Types of disuse (spinal cord injury, causes type 1 fiber atrophy with slow-to-fast fiber type shift); specific muscles

123
Q

What are disuse effects on muscle function

A

performance (strength, size, endurance), muscle quality (?)

124
Q

What type of atrophy do you get with spinal cord injury

A

type 1 fiber atrophy with slow-to-fast fiber type shift

125
Q

What type of atrophy do you get with cancer

A

type 2 fibers with fast-to-slow fiber type shift

126
Q

specificity

A

the adaptation of the body or change in physical fitness is specific to the type of training undertaken

127
Q

Hypertrophy vs Atrophy balance

A

balance between protein synthesis and protein breakdown (towards breakdown)

128
Q

Hypertrophy

A

select fibers get larger, nuclei are added to normalize myonuclear domain size

129
Q

Hyperplasia

A

Increase in number of muscle fibers

130
Q

Blood markers of muscle

A

CK, Myoglobin (radioimmunoassay), Lactate dehydrogenase, Troponin

131
Q

Problem of blood markers

A

Variability (only used semi-quantitatively)

132
Q

Indirect Damage Markers - Muscles

A

Force loss, soreness, muscle problems in blood, inflammation, neuromuscular changes

133
Q

Direct Damage Markers - Muscles

A

confocal/light microscopy, electron microscopy, IHC

134
Q

Muscle Damage: Biceps Model

A

Maximal eccentric actions of the elbow flexors

135
Q

Repeated Bout Effect Mechanism

A

Neural adaptation, Tissue-level adaptation, Sarcomere-level adaptation, Systemic adaptation

136
Q

Neural Adaptation

A

RBE effect present w/ electrically stimulated contractions

137
Q

Tissue-level adaptation

A

Altered passive stiffness/ECM

138
Q

Sarcomere-level adapation

A

“popped” sarcomeres

139
Q

Systemic adaptation

A

altered inflammatory response

140
Q

Fatty acid oxidation ____ with obesity

A

Decreases

141
Q

Most muscles (in humas) have _____ fiber type compositions

A

mixed

142
Q

Muscles fibers vary by their favored source of fuel - ______

A

glycolytic (CHO) vs. oxidative

143
Q

What effects are additive with exercise

A

insulin

144
Q

Shorter exercise fuel source

A

carbs

145
Q

Skeletal Muscle glucose uptake’s basal activity is is largely regulated via _____

A

GLUT1

146
Q

Skeletal Muscle glucose uptake’s contraction (activity) is regulated by what?

A

insulin signals translocation of GLUT4 glucose receptors to surface

147
Q

Hyperglycemia

A

High blood glucose after a meal

148
Q

Hypoglycemia

A

Low blood glucose after fasting

149
Q

Reactive hypoglycemia occurs when

A

crashing after a meal
high glucose –> insulin –> too much glucose cleared from blood –> low blood glucose

150
Q

Pancreas secretes _____ to bring blood glucose back down to normal

A

insulin

151
Q

Pancreas secretes _____ to bring blood glucose back down to normal

A

glucagon

152
Q

Insulin secreted by ______

A

beta cells (pancreas)

153
Q

Insulin does what?

A

Stimulates glucose transporters to help take glucose from the blood across the cell membrane

154
Q

Which hormones control blood glucose levels:

A

Insulin, Glucagon, Epinephrine, NE, Cortisol

155
Q

Where is blood glucose stored

A

muscle and liver (converted to glycogen)

156
Q

What could happen to blood glucose?

A

stored muscle/liver (glycogen), converted to fat, excreted, used immediately for energy (muscle and brain cells)

157
Q

Three key enzymes that regulate glycolysis

A

Hexokinase, Phosphofructokinase, Pyruvate kinase

158
Q

What is Hexokinase inhibited by

A

glucose-6-phosphate

159
Q

What is Phosphofructokinase inhibited by

A

iATP, citrate, and H+

160
Q

What is pyruvate kinase inhibited by

A

ATP

161
Q

What is pyruvate kinase activated by

A

fructose-1,6-bisphophate

162
Q

What are the net products of glycolysis

A

2 ATP, 2 pyruvate, 2 NADH

163
Q

What are your glucose sources

A

Muscle glycogen, blood glucose, liver glycogen

164
Q

What are the net products from one glucose in the lactic acid system (anaerobic metabolism)

A

2 ATP

165
Q

What are the net products from one glucose in the oxygen system (aerobic metabolism)

A

32 ATP

166
Q

how are proteins as an energy source

A

Not a good first choice (15%) - must break down into AA then transform into acetyl CoA

167
Q

How are lipids as an energy source

A

Only use oxidative metabolism, main form of storage and exchange is triglycerides

168
Q

Explain fat breakdown for energy

A

must free FA from backbone, beta oxidation cuts FA into 2C pieces (acetyl CoA) to be used in Krebs cycle

169
Q

The longer the fatty acid, ____

A

the greater the ATP return

170
Q

Describe CHO breakdown for energy

A

can be broken down without o2 using glycolysis- break 6C glucose –> 2 3C pyruvate (2 ATP net gain) further process pyruvate using O2

171
Q

What is unique about CHO as an energy source

A

only nutrient that can create energy via both anaerobic and aerobic processes

172
Q

Where is glucose for CHO breakdown stored

A

in muscle as muscle glycogen

173
Q

What is CHO’s storage form

A

Glycogen

174
Q

What is fat’s storage form

A

Triglycerides

175
Q

What is protein’s storage form

A

Tissue

176
Q

What are dietary sources of creatine metabolism

A

Meat and fish

177
Q

What is PCr

A

Phosphocreatine - a spatial and temporal buffer

178
Q

What can PCr do

A

can rapidly replenish ATP from ADP + PCr –> ATP + Cr

179
Q

Autogenic inhibition reflec

A

a sudden relaxation of muscle at very high muscle tension (protects against muscle tears)

180
Q

What does increased muscle tension cause in GTO

A

compress nerve endings, opening stretch sensitive ion channels

181
Q

What are GTO formed by branches of

A

Type Ib afferent fibers

182
Q

GTO organs only affect _____

A

individual muscle (adjacent muscles are not affected)

183
Q

What does coactivation of alpha and gamma motor neurons prevent

A

prevents spindle from being unloaded during contraction, hence proper damping function of spindle is maintained

184
Q

what is the strecth reflex response

A

contraction of muscle

185
Q

What does sudden stretch of the muscle excite

A

muscle spindle

186
Q

afferent impulses to the spinal cord excite ____ to result in contraction of the muscle

A

a-motor neuron

187
Q

what happens at the same time in the stretch reflex

A

synergistic muscles are activated, antagonistic muscles are inhbited

188
Q

What the afferents in the static response

A

Type Ia

189
Q

What are the afferents in the dynamic response

A

Type Ia and Type II

190
Q

Integrin extracellular binding activity is regulated from where?

A

inside the cell

191
Q

What does integrin binding to the ECM do

A

indues signals that are transmitted into the cell

192
Q

List the steps in Neurotransmission

A

AP, Opening of voltage-gated CA channels/influx of Ca into presynaptic terminal, release of ach to cleft, ach binds with nicotinic receptors on postsynaptic membrane (ach-receptor complex), Na inyo post-synaptic cell, Endplate potential (change in MP of myofiber),generate muscle AP, muscle contraction

193
Q

What is the action of Fast K+ channels in striated muscle

A

terminates AP

194
Q

What is the action of Inward K+ channels in straited muscle

A

stabilizes membrane potential; increases K+ entry in fatigue

195
Q

What is the action of ATP sensitive K+ channels in straited muscle

A

stabilizes membrane potential; increases K+ entry in fatigue

196
Q

What is the action of Na+ activated K+ channels in straited muscle

A

stabilizes membrane potential; increases K+ entry in fatigue

197
Q

What is the action of ATP sensitive K+ channels in straited muscle

A

stabilizes membrane potential; reduces Ca+ entry

198
Q

WHat is the gating mechanism for ATP sensitive K+ channels in straited muscle

A

decreased ATP and ph

199
Q

What is the Na/K pump activated by?

A

increase in cell volume

200
Q

How does sodium-potassium pump play a role in osmotic balance

A

Na (3) out of cell and K (2) into cell

201
Q

What does binding of the DHP receptor to the ryanodine receptor in muscle cells do

A

releases CA ions from the SR (active troponin to release from tropomyosin)

202
Q

What does tropomyosin do when it troponin has been released from it

A

shift position, allowing myosin heads to attach to the actin filament

203
Q

Where is the location of Troponin C

A

Actin filaments

204
Q

What is the function and location of Calsequestrin

A

Sequesters Ca2+ within SR

205
Q

What is the function and location of parvalbumin

A

cytoplasm, accelerates relaxation

206
Q

What is the function and location of calmodulin

A

cytoplasm, modulates protein kinase (and other enzymes)

207
Q

The motor cortex is divided into ____ subareas

A

3 (primary, premotor, supplemental)

208
Q

what is the function of the primary motor cortex

A

fine motor movement elicited by stimulation

209
Q

what is the function of the premotor area

A

movement of muscle groups to perform a specific task

210
Q

what is the function of the supplemental motor area

A

functions in concert with premotor area to provide attitudinal, fixation, or positional movement of the body

211
Q

what does the supplemental motor area provide the background for

A

fine motor control of the arms and hands by premotor and primary motor cortex

212
Q

what does stimulation of the supplemental motor area elicit

A

attitudinal, fixation, or positional movement for the body

213
Q

what does damage to Broca’s area cause

A

decreased speech capability

214
Q

what does damage to the hand skills area cause

A

motor apraxia (the inability to perform fine hand movements)

215
Q

what is the direct pathway to transmit cortical motor signals

A

corticospinal tract

216
Q

what type of movements is the corticospinal tract for

A

discrete detailed movements

217
Q

where does the indirect pathway signal to for the transmission of cortical motor signals

A

signals to basal ganglia, cerebellum, and brainstem nuclei

218
Q

describe the fibers in the cotricospinal tract

A

majority of fibers cross to the opposite side in the medulla and descend in the lateral corticospinal tracts

219
Q

what cells give rise to large fibers with fast transmission rates in the corticospinal tract

A

Giant pyramidal cells (Betz cells)

220
Q

what do cortiospinal neurons synapse with

A

interneurons anterior motor neurons and a few sensory relay neurons in cord gray matter

221
Q

what do MOST corticospinal neurons synapse with

A

interneurons

222
Q

some corticospinal and rubrospinal neurons synapse directly with ______ (esp. in the cervical enlargement)

A

alpha motor neurons

223
Q

corticospinal neurons that synapse directly with alpha motor neurons in the spinal cord (esp. within the cervical enlargement) innervate what muscles?

A

hand and fingers

224
Q

what are incoming sensory pathways to the motor cortex

A

subcortical fibers from somatic sensory areas (opposite hemispheres - pass through the corpus callosum), somatic sensory fibers from the thalamus, ventrolateral and ventroanterior nuceli of thalamus, fiebrs from the intralaminar nuclei of the thalamus (some may be pain)

225
Q

excitation of what is needed to cause muscle contraction

A

50-100 giant pyramidal cells

226
Q

where does sensory feedback important for motor control (fine tune muscle movement) come from

A

muscle spindle, tactile receptors, and proprioceptors

227
Q

what causes auto-correction in terms of feedback for motor control

A

length mismatch

228
Q

what would a lesion to the primary motor cortex cause

A

loss of voluntary control of discrete movement of distal segments of the limbs

229
Q

what would a lesion to the basal ganglia cause

A

muscle spasticity from loss of inhibitory input from accessory areas of the cortex that inhibit excitatory brainstem motor nuclei

230
Q

what does stimulation of the red nucleus cause

A

relatively fine motor movement (but not as discrete as primary motor cortex)

231
Q

what is the accessory route for transmission of discrete signals from the motor cortex

A

red nucleus

232
Q

what is the red nucleus and the rubrospinal tract

A

substantial input from the primary motor cortex

233
Q

brainstem is an extension of the _____

A

spinal cord

234
Q

what is the function of the brainstem in motor function

A

performs motor and sensory functions for the face and head (cranial nerves)

235
Q

what type of centers does the brainstem have for motor control

A

stereotypic movement and equilibrium centers

236
Q

what is within the utricle and saccule in the vestibular apparatus

A

sensory organs for detecting the orientation of the head with respect to gravity (macula)

237
Q

what is the vestibular apparatus

A

system of bony tubes and chambers in the temporal bone

238
Q

what does the vestibular apparatus contain

A

semicircular ducts, utricle, saccule

239
Q

how is information from the hair cells in the inner ear transmitted to the brain

A

vestibular nerve

240
Q

when the body is accelerated forward, the hair cells of the maculae bend _____

A

backwards (falling backward feeling; reflex causes body to lean foward)

241
Q

what is the cerebellum responsible for

A

coordinating muscle activity and sequencing motor activities

242
Q

what does the cerebellum do to make corrective changes

A

compares actual motor movements with intended movements (monitors and makes corrective adjustments in activities initiated by other parts of the brain)

243
Q

what is the vermis (located in the center) of the cerebellum control

A

controls axial movements of the neck, shoulders, and hips

244
Q

what is the intermediate zone of the cerebellum controlling

A

motion of distal portions of upper and lower limbs (esp. hands and feet)

245
Q

what does the lateral zone of the cerebellum contol

A

sequencing movements of the muscle (important for timing and coordination of the movement)

246
Q

What are the efferent pathways from the cerebellum

A

fastigoreticular tract and cerebellothalamocortical tract

247
Q

what does the fastigoreticular tract do

A

controls equilibrium

248
Q

what does the cerebellothalamocortical tract do

A

coordinates agonist and anatagonist muscle contractions

249
Q

what are the afferent pathways to the cerebellum

A

dorsal and ventral spinocerebellar tracts

250
Q

where does the dorsal spinocerebellar tract transmit information from

A

muscles spindle but also from GTO, tactile, and joint receptors

251
Q

where does the ventral spinocerebellar tract transmit information from

A

signals from anterior horn and interneurons

252
Q

what information does the ventral spinocerebellar tract transmit

A

information on which signals have arrived at the cord

253
Q

what information does the dorsal spinocerebellar tract transmit

A

apprises the brain of momentary status of muscle contraction, muscle tension, and limb position and forces acting on the body surface

254
Q

what is the neuronal organization of the cerebellar cortex

A

molecular, purkinje, granular cell layers

255
Q

where does the output from the cerebellum come from

A

comes from a deep nuclear cell layer located below the layers of cortex

256
Q

what are the four functional sections of the basal ganglia

A

striatum (caudate and putamen), globus pallidus, substaintia nigra, subthalamus

257
Q

what is the motor function of the basal ganglia

A

control complex patterns of motor activity (help to match learned patterns - throwing balls, wiritng)

258
Q

athetosis

A

spontaneous writing movements of the hand, arm, neck, and face

259
Q

chorea

A

flicking movements of the hands, face, and shoulders

260
Q

Parkinson disease

A

rigidity, tremor, akinesa (loss of dopamingeric input from substantia nigra to the caudate and putemen)

261
Q

what would a lesion to the globus pallidus cause

A

athetosis

262
Q

what would a lesion to the substantia nigra cause

A

Parkinsons disease

263
Q

what would a lesion to the putamen cause

A

chorea

264
Q

what would a lesion to the caudate nucleus and putament cause

A

Huntingtons chorea

265
Q

what would a lesion to the subthalamus cause

A

hemiballismus

266
Q

hemiballismus

A

sudden flailing movements of the entire limb

267
Q

Huntington chorea

A

los of GABA containing neurons to globus pallidus and substantia nigra

268
Q

how does the brain stem level of motor control maintain equilibrium

A

adjusting axial tone

269
Q

what role does the cortical level play in integrating motor control

A

issues commands to set into motions the patterns available in the spinal cord and controls intensity and modifies the timing

270
Q

what role does the cerebellum play in integrating motor control

A

adjust cord motor activity, equilibrium, and planning of motor activity

271
Q

How does the deep nuclear cell activity work in motion

A

at beginning of motion there is excitatory signals sent into motor pathway by deep nuclear cell to enhance movement, followed by inhibitory signals milliseconds later (provides dampaning function to stop movement from overshooting mark)

272
Q

what is the function of purkinje cells

A

correct motor errors (listen to feedback tracts)

273
Q

what does climbing fiber input in purkinje cells do

A

adjusts the sensitivity of purkinje cells to stimulation of parallel fibers (changes long-term sensitivity to mossy fiber input)

Semester 2 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions