Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Histology Exam 2 - Brendan > Muscle > Flashcards

Muscle Flashcards

(88 cards)

Start Studying
1
Q

Muscle is surrounded by a dense connective tissue layer called ____

A

epimysium

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

muscle consists of _____ ______ bundles (Fascicles) surrounded by ______

A

muscle fiber

perimysium

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

_____ ______ ______ consist of individual multinucleated muscle fibers 10-100 um wide and up to 30 cm long.

A

Muscle fiber bundles

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

Muscle cells are surrounded by a ______ _____ and reticular fibers that make up the _____

A

basal lamina

endomysium

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

endomysium contains _____ that supply blood to the muscle fiber

A

capillaries

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

Complete the “muscle flow chart”

  1. _____ (surrounded by epimysium)–>
  2. ______ (surrounded by perimysium) –>
  3. _____ (Surrounded by endomysium) –>
  4. _______
  5. _______
A 
muscle
muscle fiber bundle aka fascicle
muscle fiber aka muscle cell
myofibril
myofilament
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

_____ cells are infrequent small cells found between the sarcolemma and basal lamina. They are stem cells that can proliferate after trauma and form new _____

A

satellite

myoblasts

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

In LM with H and E staining, A bands stain _____ while I bands are _____. A dark ___ line may be seen bisecting the I band.

A

dark
light
Z

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

The _____ is the functional unit of contraction, and runs from ____ to _____

A

sacromere

z-disk to z-disk

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

The ____ _____ is in the middle of I bands and is where actin filaments insert

A

Z disk

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

Skeletal muscle has a well developed _____ system.

A

Triad

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

The inner portion of the triad in skeletal muscle is an infolding of the plasma membrane called a ___ ____. The 2 triad side portions are modified smooth ER called ____ ______

A

T-tubule

sarcoplasmic reticulum

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

The triad system in skeletal muscle is found in the ___ ____ band junction

A

A and I

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

The interaction between nerve axon and muscle is called the ____ ____ ____ (aka myoneural junction)

A

motor end plate

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

Axon loses myelin sheath near the muscle cell, but ____ ____ still cover the axon

A

schwann cells

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

At the motor end plate, the axon and schwann cells (aka teloglia) basal lamina fuse with the ____ _____

A

muscle fiber

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

Axon terminals contain ____ which diffuses across the synaptic cleft and binds to receptors in ____ _____ of the sarcolemma

A

acetylcholine

junctional folds

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

The nerve and the muscle fibers it innervates is called a ____ _____

A

motor unit.

a single axon can innervate multiple muscle fibrs

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

____ ____ binds to the pre-snyaptic membrane, blocking ACH release

A

botulism toxin

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

Both the _____ _____ autoantibody and ______ bind to ACH receptors

A

myasthenia gravis

curare

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

Mysathenia gravis contains antibodies that block ____, leading to _____ ____ _____

A

acetylcholine

progressive muscle weakness

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

The action potential generated at the motor end plate is propagated along the _____ and is carried into myofirbils by the ____ __ _____ system (located at junction of A and I band) that is continuous with the myofibril _____

A

sarcolemma
transverse t tubule
sarcolemma

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

Depolarization of the T-tubule system causes release of ____ from ____ ______ of the sarcoplasmic reticulum

A

Calcium

terminal cisternae

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

The release of Ca causes conformational changes in troponin-__ that mediate the interaction of actin and ____, causing muscle contraction

A

C

myosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
___ fibers are Type 1 and slow twitch. They have ____ myoglobin content and _____ mitochondria. They are fatigue _____. They stain strongly for mitochondrial enzymes such as _____ ______
``` red high numerous resistant succinate dehydrogenase ```
26
White fibers are type __ and ____ twitch. They have _____ myoglobin and mitchondria content, but have more stored ______ than red fibers. They also have higher ____-_____ than Type 1
2, fast lower glycogen myosin ATPase
27
_____ controls fiber type differentiation.
innervation ie, a red fiber can be changed to a white by denervating and replacing with nerve from white fiber
28
____ _____ are sensory receptors that run parallel with the main muscle fibers. They sense changes in ____ _____
``` muscle spindles muscle length (ie stretch receptors) ```
29
Muscle spindles contain modified muscle fibers called ____ fibers and neuron terminals in a fluid filled CT capsule.
intrafusal
30
The nerve terminal discharge rate _____ as the sensory ending is stretched. The nerve terminal has a ______ ending
increases | annulospiral
31
There are 2 types of intrafusal fiber: _____ _____ and ____ _____
nuclear bag and nuclear chain
32
After muscle injury, ____ transcription factor in combination with ___ _____ ____ induces proliferation of satellite cells (quiescent myoblasts).
myoD | hepatocyte growth factor (HGF)
33
In rigor mortis (after death), muscle cell membranes become ____ permeable to Ca. This promotes the cross-bridge attachment between ___ and ____.
more | actin and myosin
34
Rigor mortis--msucle fibers contract while Ach and ATP are present or until fully contracted. Muscles use ATP to pump ____ out of the cells, and once the ATP is used up, the actin and myosin proteins will stay ____ until decomposition
calcium | linked
35
Muscle atrophy is due to disuse and is caused by a reduction in _____ _____ _____
muscle fiber size. | the number of muscle fibers doesn't change
36
Myofirbils consist of myofilaments that contain 4 main proteins:
actin, tropomyosin, troponin (thin) | myosin (Thick)
37
____ is an elastic protein that connects myosin to Z-disk. It acts like a spring to keep ____ filaments centered in the sarcomere
titin | myosin
38
____ is an INELASTIC protein attached to the Z-disk that runs parallel to actin
nebullin
39
___ is a mysoin binding protein that holds myosin filaments in register at the M-line
myomesin
40
__ _____ is a myosin binding protein that functions similarily to myomesin
c protein
41
___ ___ bundles actin filaments into parallel arrays and anchors them to the Z-disk
alpha actinin
42
____ is an IF that helps bind myofibrils to each other. It also encircles the Z disk. It is linked to each other by _____
desmin | plectin
43
_____ is an actin binding protein that anchors muscle membrane proteins to actin. It
dystrophin it is ABSENT in duchenne muscular dystrophy
44
The _ ____ is the only band that contains thick filaments. It also contains thin myofilaments
A band
45
the _ band consists of thin myofilaments attached to the Z disk that extend to the A band.
I
46
the _ band contains myosin (with no heads) and ____ ____ that catalyzes ATP formation from ADP and phosphocreatine
H | creatine kinase
47
The _ ____ is a region of myomesin linking with myosin. It is located within the H band
M line
48
The _ ____ is the attachment region of thin filaments that contains __ _____
Z disk | alpha actinin
49
Polymerization of actin in vivo is regulated by _____ and ____ and other cytosolic proteins
thymosin | profilin
50
_____ is an elongated protein dimer that lies in grooves of the actin helix
tropomyosin
51
Tropomyosin molecoule binds 3 troponin (Tn) peptides: Tn-_ binds the Tn complex to tropomyosin Tn-_ with tropomyosin inhibits the binding of actin to myosin Tn-_ is the calcium binding subunit
T I C
52
Binding of Calcium to the Tn-C subunit releases the TnI tropomyosin inhibition of actin activation of ___ ____
myosin ATPase
53
___-_____ is a heat shock protein that protects desmin from stress-induced damage
alphabeta-crystallin
54
____ reinforces and stabilizes the sarcolemma during contraction by linking the cytoskeleton with the ECM. Defective or lack of this protein disrupts sarcolemma and Ca entrance into the cell, leading to ____ ____ ____
dystrophin muscle fiber necrosis (ie this is duschennes muscular dystrophy)
55
________ (aka limb-girdle muscular dystrophies) are mutations in genes for sarcoglycans, which disrupts the association of sarcolemma with ____
sarcoglycanopathies | ECM
56
Myosin is the thick myofilament. It is both a ____ ____ and a ____ ____ ____
globular enzyme | fibrous structural protein
57
Myosin consists of ___________ and ________
2 identical heavy and 2 pairs of light chains
58
___ ____ contains the ATP and actin binding region
heavy meromyosin
59
In striated muscle, myosin forms ____ ____
bipolar filaments
60
muscle contraction--Ca released from the SR after membrane depolarization binds to the __-__ subunit of troponin
Tn-C
61
Binding of the Tn-C unit with calcium causes a configuration shift of ____ and moves the tropomyosin molecoule deeper into the actin helix groove and exposes the ____ binding site on actin
troponin | myosin
62
myosin binds to actin and the energy yielding breakdown of ___ to ____ flexes the ____ head and actin thin filaments are pulled into the a-band.
ATP to ADP | myosin
63
A new ATP molecoule binding the myosin head causes the release of the bond between ___ and ____
actin and myosin | After contraction
64
Cardiac muscle consists of ___ (1/multiple) nucleus/nuclei ____ located in the cell
1 | centrally
65
Cardiac muscle fiber is composed of several cardiac muscle cells joined end to end by junctional zones called ___ ____
intercalated disks
66
intercalated disks have a transverse portion which contains ____ ____ and ___ ___ that bind adjacent cells together
fascia adherens | macula adherens
67
intercalated disks contain a transverse portion and a lateral portion that contains ___ ____ that ionically couple adjacent cells
gap junctions
68
A hallmark of cardiac muscle is ___ _____ _____
branched muscle fibers
69
Cardiac muscle has more ____ and extrafibrillar sarcoplasm than skeletal muscle
mitochondria
70
In cardiac muscle, the T-tubules are larger than in skeltal muscle and are located at the level of the __ _____
Z disk
71
A ____ arrangement is more common in cardiac muscle
diad
72
cardiac muscle responds to injury by forming a ____ ____ ____ ____. Under normal conditions, cardiac muscle does/does not regenerate
fibrous connective tissue scar | does not
73
In skeletal muscle, all Ca ions come from the SR. In hear muscle, Ca ions can come from the SR as well as ___ ___ via slow ion channels
extraceullar fluid
74
After myocardial infarction, cardiocytes have a _____ cytoplasm and ____ nuclei
eisonophillic | pyknotic (whatever that means)
75
after 3 days from an MI, ___ ___ infiltrate cardiac tissue
inflammatory cells
76
smooth muscle cells are ____ shaped but may branch. They contain a single ____ oval nucleus with 1 or more _____.
spindle central nucleoli
77
smooth muscle cells are surrounded by a ___ ___ and may secrete collagen and elastin
basal lamina
78
2 smooth muscles cells in contact may form ___ ____ and interdigitations that facillitate electrical conduction
gap junctions
79
the plasma membrane of smooth muscle cells contain numerous ____ on the surface and ____ ____ in cytoplasm that contain alpha actinin.
caveolae | dense bodies
80
Single smooth muscle cells are myoepithelial cells of ____ origin, found around sweat, salivary, lacrimal, and mammary glands, as well as the iris and cilliary body of the eye. They are basket shaped cells which contain ____ that attach them to basal lamina.
ectodermal | hemidesmosomes
81
In mammary glands, smooth muscle cells contract in response to _____ and in lacrimal glands, they respond to _____
oxytocin | acetylcholine
82
smooth muscle cells of ____ origin are located in respiratory, circulatory, digestive, and reproductive tracts
mesodermal
83
Smooth muscle does not contain _____. The functional equivalent of the Z-disk is ___ _____
sarcomeres | alpha actinin
84
Smooth muscle cytoplasm contains bundles of thin filaments (actin and tropomyosin but not _____), IF (desmin and _____) and thick filaments (____)
troponin vimentin myosin
85
If smooth muscle myosin is _____, it is completely soluble
dephosphorylated
86
Smooth muscle contraction--when stimulated, calcium increases in the cytoplasm and complexes with ____
calmodulin
87
The Ca-calmodulin complex activates ___ ____ ____ ____, causing myosin to unfold and form filaments, allowing it to interact with actin
myosin light chain kinase
88
___ may also activate myosin light chain kinase
cAMP

Histology Exam 2 - Brendan (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions