Brainscape's Knowledge GenomeTM

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


See full index

Histology > Muscle > Flashcards

Muscle Flashcards

1
Q

individual muscle cell is called

A

myocyte

muscle fiber

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

muscle cytoplasm=

A

sarcoplasm

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

muscle plasma membrane/plasmalemma=

A

sarcolemma

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

3 types of Mm

A

skeletal
smooth
cardiac

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

all three types of muscle are derived from the

A

mesoderm

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

skeletal muscle is responsible for the

A

movement of skeleton

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

skeletal muscle is under

A

voluntary motor control

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

–% of the body mass is skeletal mm

A

40%

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

skeletal mm cells nuclei are

A

multinucleate

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

multinucleate cells form

A

syncytial

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

syncytial forms due to

A

fusion of myoblasts into a multinucleate myotube during development

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

myotubes synthesize

A

contractile proteins which assemble sarcomeres

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

skeletal muscle nuclei migrate to the

A

periphery of the cell

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

skeletal muscle nuclei lose the ability to

A

proliferate

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

individual muscle fibers are surrounded by connective tissue called

A

endomysium

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

several fibers bound together into

A

fascicles

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

fascicles surrounded by connective tissue

A

perimysium

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

many fascicles together form

A

muscle

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

entire muscle surrounded by

A

epimysium

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

epimysium is continuous with

A

tendinous attachment

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

blood vessels and Nn tend to follow connective tissue epi and perimysial for

A

support

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

two types of skeletal muscle fibers

A

fast twitch

slow twitch

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

Early in development of myotubes, “fast” Mm fibers are innervated by “—” Nn & “slow” Mm fibers by “—” Nn

A

fast

slow

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

Also differences in development of contractile proteins

A

“fast” myosin & “slow” myosin

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

slow myosin are — fibers with a large amount of —

A

small

myoglobin

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

type 1 uses — — — for oxidative metabolism

A

1’ aerobic respiration

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

type 1 have a large number of mitochondria, used for

A

ATP

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

type 1 muscle fibers are resistant to

A

fatigue

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

type 1 muscle fibers generate — muscle tension

A

moderate

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

where are type 1 slow fibers common?

A

in peripheral limbs

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

color of type 1 slow twitch fibers

A

dark red, almost black bc they’re rich in myoglobin

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

type 2 fibers are — fibers with — myoglobin and — mitochondria

A

large
less
fewer

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

how do type 2 fibers use — — — for energy production

A

1’ anaerobic glycolysis

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

type 1 fibers have abundant

A

glycogen

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

type 2 have extensive sarcoplasmic reticulum for rapid

A

ca release

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

type 2 fibers fatigue

A

readily

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

type 2 fast twitch fibers generate — muscle tension for short bursts of activity

A

high

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

intermediate filaments (2)

A

type 2a

type 2b

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

type 2a

A

oxidative and fatigue resistant

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

type 2b

A

glycolytic and fatigue sensitive

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

most muscles are

A

mixed

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

during peak periods of exertion, both type 1 and 2 fibers metabolism glycogen via

A

anaerobic glycolysis to produce ATP

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

intermediate metabolites (lactic acid) predicate as crystals in muscle, leading to

A

tearing of muscle fibers and pain after heavy exertion

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

if oxygen debt is severe, it can lead to (3)

A

ischemia
muscle cramps
cell death

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

extreme exertion may lead to (2) due to the release of myoglobin and clogging of glomeruli

A

acute rhabdomyolysis and subsequent myoglobinuric nephrosis

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

acute rhabdomyolysis

A

breakdown of actin and myosin

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

myoglobinuric nephrosis

A

kidney failure

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

during normal exercise, muscle fibers develop

A

microtears

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

hypertrophy

A

with exercise, muscle cells increase in size

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

why do muscle fibers increase in size? (3)

A

increase in number of mitochondria
increase in volume of contractile proteins
splitting/branching of individual muscle fibers

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

production of new muscle fibers is relatively

A

rare

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

atrophy

A

with disuse, muscle cells decrease in size

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

why do muscle cells decrease in size? (2)

A

immobilization (splint, cast)

denervation (never damage least to muscle atrophy)

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

sarcopenia

A

with increased age, progressive loss of skeletal muscle fibers `

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

lost muscle fibers are not replaced, therefore

A

increase in number and decrease in size of muscle mass

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

skeletal muscle ability to regenerate following injury

A

limited ability

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

primary source of regeneration

A

satellite cells

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

satellite cells

A

small myogenic cells adjacent to sarcolemma

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

after injury, cells proliferate and differentiate into

A

myoblasts

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

– types of proprioceptors located within mm

A

2

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

intrafusal fibers

A

modified skeletal muscle fibers associated with modified nerve endings

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

neuromuscular spindles

A

muscle spindles

located within belly of mm

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

neuromuscular spindles are sensitive to changes in

A

length

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

neurotendinous spindles

A

Golgi tendon organs

located within tendon

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

neurotendinous spindles are sensitive to changes in

A

tension

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

both prevent overstretching and tearing of mm; used in (2)

A

postural reflexes

coordination

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

individual muscle fibers are composed of

A

myofibrils

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

myofibrils are composed of numerous

A

myofilaments or contractile proteins in parallel bundles

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

two types of myofilaments

A

actin

myosin

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

actin

A

thin filament

6-8 nm in diameter

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

myosin

A

thick filament

15 nm in diameter

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

actin and myosin ratio is skeletal muscle

A

2:1

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

striated muscle

A

parallel arrangement of contractile proteins which give a striated appearance in longitudinal section

74
Q

actin and myosin overlap in the - band but not the - band

A

A band
I band
(striations)

75
Q

skeletal muscles are stopped in C-S due to

A

hexogonal array of microfilaments

76
Q

myofibrils are arranged in

A

sarcomeres

77
Q

sarcomeres

A

the functional units of muscle cells

78
Q

z discs act as anchoring points for

A

actin myofilaments

79
Q

during muscle contraction, sarcomeres shorten, but — remain the same length -

A

myofilaments

80
Q

due to thick and thin filaments sliding over one another via energy from ATP,

A

shortening of sarcomere, via repeated binding and unbinding of actin and myosin filaments

81
Q

neuromuscular junction (NMJ)

A

the site where skeletal muscle is innervated by motor neurons

82
Q

motor end plate

A

dilated terminal portion of axon surrounded by myelin

83
Q

the motor end plate rests on

A

sarcolemma

84
Q

terminal button is similar to the motor end plate, except

A

unmyelinated

85
Q

synaptic cleft

A

the space between the motor end plate of neurons and sarcolemma of muscle

86
Q

which chemical neurotransmitter is the neuromuscular junction typically bridged by?

A

acetylcholine

87
Q

what does the depolarization of the muscle fiber travel down?

A

transverse tubule system (t tubules)

88
Q

t tubules

A

extensive network of tubules continuous with the sarcolemma

89
Q

t tubules indirectly links the extracellular space with (2)

A

ER

intracellular environment

90
Q

ends of t tubules are bounded by enlarged

A

terminal cistern of either side

91
Q

triad

A

2 terminal cisternal and one t tubule

92
Q

sarcoplasmic reticulum and terminal cisternal act as – reservoirs when muscle is relaxed

A

ca

93
Q

– is necessary for muscle contraction

A

ca

94
Q

influx of sodium ions into the cytoplasm from t tubules trigger depolarization of

A

sarcolemma

95
Q

depolarization of sarcolemma releases – from the ER and terminal cisternae into the cytoplasm during contraction

A

ca

96
Q

what do ca ions activate?

A

sliding filament mechanism during contraction

97
Q

how does ca activate the sliding filament mechanism?

A

ca causes conformational change in troponin which interacts with tropomyosin molecules (bound to actin), exposing myosin binding site on actin filament. myosin binding causes conformational change in myosin head and sliding of myosin past actin. myosin heads repeatedly bind and unbind to actin in the presence of ca and pi causing contraction

98
Q

all or none response

A

muscle fiber either contracts or it doesn’t

99
Q

total number of muscle fibers contracting at any given time determines the

A

strength of overall contraction

100
Q

graded response

A

strength of overall contraction

101
Q

motor unit

A

a group of muscle fibers supplied by a single motor neuron

102
Q

stimulation of a motor neuron results in contraction of — muscle fibers within the motor unit

A

all

103
Q

– of motor units varies

A

size

104
Q

recruitment increases the number of

A

motor units firing within a muscle

105
Q

muscular dystrophy

A

degenerative wasting disease
muscle weakness due to genetic defect in muscle protein
cell dead

106
Q

what form of muscular dystrophy affects protein?

A

dystrophin

107
Q

myasthenia graves

A

autoimmune disease caused by production of antibodies to act receptors resulting in muscle weakness

108
Q

treatment of myasthenia graves

A

achase inhibitors

109
Q

inherent contractility

A

rhythmic, wave like contractions independent of neurological stimulation

110
Q

smooth muscle organization

A

endothelial peri epi

111
Q

smooth muscle fibers are bound together into highly irregular, branching fascicles specialized for

A

prolonged contractions with low force

112
Q

smooth muscle nucleus

A

single, long, central

113
Q

are skeletal or smooth muscle fibers larger?

A

skeletal

114
Q

actin and myosin ratio in smooth muscle

A

15:1

randomly arranged

115
Q

arrangement of smooth muscle

A

random
myofilaments are not arranged in sarcomeres
no striations

116
Q

dense bodies

A

equivalent functionally to z discs

provide attachment sites for actin

117
Q

smooth muscle lacks

A

troponin complex that controls myosin binding

118
Q

instead of troponin, smooth muscle uses

A

calmodulin

119
Q

calmodulin

A

binds ca and activates myosin cross binding

120
Q

smooth muscle lacks t tubule system and terminal cisternal of ER. instead, cell membrane has

A

caveolae

121
Q

caveolae

A

pockets/ divets in the membrane

122
Q

what does smooth muscle rely on for contraction?

A

extracellular ca

123
Q

what is smooth muscle influenced by? (3)

A

autonomic nervous system
hormones
local metabolites

124
Q

smooth muscle autonomics

A

most has dual sympathetic and parasympathetic innervation

125
Q

is smooth muscle voluntary?

A

no, involuntary

126
Q

response of smooth muscle depends on

A

receptor tupe (alpha or beta)

127
Q

sympathetic stimulation in the gut leads to

A

inhibitory and parasympathetic stimulation, then stimulation to Smooth muscle

128
Q

smooth muscle as a single unit

A

tonic smooth muscle
fibers contract as a unit
ex. visceral smooth muscle of the gut, most common

129
Q

smooth muscle as a multi unit

A

phasic smooth muscle
individual muscle fibers contract independently
ex. ciliary body of iris, erector pili muscle

130
Q

smooth muscle retains the ability to divide and repair itself following

A

injury

131
Q

smooth muscle cells can develop from (3)

A

endothelial cells
pericytes of blood vessels
fibroblasts

132
Q

glandular epithelial cells can also differentiate into

A

myoepithelial cells

133
Q

pericardium

A

sac like, fibrous connective tissue surrounding the heart

134
Q

layers of the heart (2)

A

fibrous connective tissue layer

inner serous layer (continuous with epicardium)

135
Q

inner serous layer contains

A

mesothelial cells

136
Q

pericardium contains

A

pericardial fluid for lubrication

137
Q

heart layers

A

epicardium
myocardium
endocardium

138
Q

epicardium

A

outermost layer, simple squamous mesothelium on the external surface of the heart

139
Q

epicardium is supported by

A

underlying fibroblastic connective tissue and adipose tissue

140
Q

blood vessels and nerves are located within

A

subepicardial layer

141
Q

the heart is surrounded by a protective layer of

A

adipose tissue

142
Q

myocardium

A

cardiac muscle itself, thicker in ventricles than atria

143
Q

what is particularly present in the myocardium?

A

endo, peri, epimysium

144
Q

the myocardium is composed of

A

fibroblasts and collagen

145
Q

cardiac muscle intermediate between skeletal and smooth muscle both

A

structurally and functionally

146
Q

cardiac muscle myocyte nucleus

A

one centrally located, occasionally two

147
Q

cardiac muscle fibers are —, but —-

A

striated

involuntary

148
Q

arrangement of contractile p[roteins into sarcomeres similar to skeletal muscle, but cardiac myocytes contain intracellular —, not —

A

diad

149
Q

diad

A

composed of one t tubule and one cisternal of ER located at the z disc

150
Q

endocardium

A

lines atria and ventricles, covers heart valves

151
Q

cell type of endothelium

A

simple squamous

152
Q

endocardium is supported by

A

sub endothelial fibroblastic connective tissue, interspersed with reticular fibers and smooth muscle

153
Q

endocardium is thicker in

A

atria than ventricles (greater turbulence in atria)

154
Q

where are purkinje fibers located?

A

within subepi and endocardial layers

155
Q

cardiac valves contain layer of fibrous connective tissue called — — covered by endothelium

A

lamina fibrosa

156
Q

valves are surrounded by tough, fibrous rings at the

A

base of the aorta and pulmonary artery (~AV valves) and extending into IVS

157
Q

occasionally ossify to form body rings at the base of AV values called

A

os cordis

158
Q

individual cardiac myocytes exhibit

A

inherent automaticity

159
Q

ends of fibers abut at

A

intercalated discs

160
Q

intercalated discs

A

unique to cardiac muscle, specialized connections between cells

161
Q

intercalated discs enhance speeds of

A

contractile stimulus between cells and allow synchronous contractions

162
Q

intercalated discs also provide increased — — for attachment of myofibrils between adjacent cells

A

surface area

163
Q

what junctions make up intercalated discs? (3)

A

desmosomes
fascia adherents
gap junctions

164
Q

desmosomes

A

macula adherents

bind individual myocytes together laterally and on the ends

165
Q

fascia adherents

A

adherent junctions

like zonula adherents but join ends of muscle fibers

166
Q

gap junctions

A

located laterally, provide iconic communication between cells, synchronize contractions, and allow muscle to behave as a syncytium

167
Q

condition system of the heart consists of (4)

A

SA node
AV node
bundle of His
purkinje fibers

168
Q

all consist of highly modified cardiac myocytes that coordinate conduction, joined by extensive

A

gap junctions

169
Q

calls larger than surrounded cardiac muscle cells conduct impulses ~-x faster

A

4x

170
Q

paler staining than surrounding muscle due to

A

higher glycogen content

171
Q

SA node

A

pacemaker

172
Q

SA node is located at junction of the

A

superior vena cava and RA

173
Q

SA node generates impulses that induce

A

contraction of atria

174
Q

as impulses travel across atria, this stimulates the

A

AV node

175
Q

AV node is located between

A

RA and V

176
Q

the AV node delays atria, giving time to

A

contract

177
Q

travels down inter ventricular septum (IVS) via

A

bundle of His

178
Q

branches into

A

Land R AV bundles within IVS

179
Q

fibers further subdivide in ventricular myocardium and ramify into — — within subendo and subepicardium of ventricular free wall, gradually merge with myocardium, initiate ventricular contraction

A

purkinje fibers

180
Q

inherent rhythm of SA node modulated by autonomic nervous system
sympathetic stimulation from:
parasympathetic stimulation from:

A

sympathetic stimulation from dympethic ganglia increase heart rate
parasympathetic stimulation from vagus nerve decrease heart rate

Histology (32 decks)

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