Brainscape's Knowledge GenomeTM

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


See full index

Zak, Cells > Exam 3: Lecture 14 > Flashcards

Exam 3: Lecture 14 Flashcards

0
Q

What is the hierarchical structure of a muscle?

A

Fasiculus->Fascile->Myofiber->Myofibril->Sarcomere->Filaments

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

List the distinctive characteristics of skeletal, cardiac, & smooth muscle.

A

Skeletal- Voluntary, striated
Smooth- Involuntary
Cardiac- Cardiac

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

What does the epimysium cover?

A

Entire muscle

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

What does the perimysium cover?

A

Fascicle

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

What does the sarcolemma cover?

A

Myofiber (muscle cell)

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

What does the endomysium cover and consist of?

A

Muscle fiber (including sarcolemma)
Consists of basal lamina & reticular collagen fibers
Basal lamina helps distribute force of contraction

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

T/F: The width of the A band decreases during contraction.

A

False, the width of the A band does not change during contraction

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

What are the characteristics of myosin thick filaments?

A

Two identical heavy chains
Head at each end
Actin, ATP, & light-chain binding regions
Essential/regulatory light chains

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

What are the characteristics of thin myosin filaments?

A

Polymer of G actin
Two polymers wound in alpha-helix
Plus end inserts on Z-disk
Troponin/tropomyosin

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

What are the 3 portions of the troponin complex and what are their functions?

A

Troponin I- Inhibits action/myosin binding
Troponin C- Binds to Ca++ ions
Troponin T- Binds to tropomyosin

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

What does titin do?

A

Provides myosin with elasticity

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

What does desmin do?

A

Provides structural strength to myofibril

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

What does plectin do?

A

Binds desmin filaments

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

What does nebulin do?

A

Controls how long actin filament gets/is

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

What are the cytoskeleton components?

A

AlphaBeta-crystallin
Dystrophin
Dystroglycan complex

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

What does AlphaBeta-crystallin do?

A

It’s a heat shock protein that protects desmin from mechanical stress

16
Q

What does dystrophin do?

A

Anchors actin to sarcolemma

Reinforces sarcolemma during contraction

17
Q

What does the dystroglycan complex do?

A

Links dystrophin (intracellular) to laminin-2 (extracellular)

18
Q

What is muscular dystrophy?

A

X-linked disease resulting in progressive degeneration of skeletal muscle

19
Q

What is the difference between Duchenne’s and Becker’s muscular dystrophy?

A

In Duchenne’s the dystrophin is absent

In Becker’s the dystophin is abnormal

20
Q

Describe the characteristics of satellite cells.

A

Become mitotic in times of stress
Found in basal lamina
Give rise to myogenic precursor cells

21
Q

Describe the characteristics of skeletal muscle

A 
Peripheral, multinucleated
Sarcomeric arrangement
Single neuron innervation
"all-or-none"
Contains troponin C
22
Q

Describe the characteristics of smooth muscle.

A 
Central, mononucleated
No sarcomeric arrangement
Innervated by ANS
Not "all-or-none"
Connected via gap junctions
23
Q

Describe the characteristics of cardiac muscle.

A

Central, mononucleated
Connected via gap junctions
Not directly innervated
Sarcomeric arrangement

24
Q

Describe Type I myofibers

A

Slow twitch, aerobic respiration
Many mitochondria
High NADH/ATPase/myoglobin
Dark/red

25
Q

Describe Type IIA myofibers.

A

Between slow/fast twitch
Both aerobic and anaerobic respiration
Resistance to fatigue

26
Q

Describe Type IIB myofibers.

A

Fast twitch, anaerobic respiration
Fatigue quickly
White/light fibers

27
Q

Describe the structure of a neuromuscular spindle.

A

Extrafusal (skeletal muscle fibers) and intrafusal fibers

28
Q

What are intrafusal fibers?

A

Nuclear bag/chain fibers

Nuclear bag contains sensory region

29
Q

Alpha-motor neurons go to _________ fibers and gamma-motor neurons go to _________ fibers.

A

Extrafusal

Intrafusal

Zak, Cells (17 decks)

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