Unit 1 Skeletal Muscle Anatomy Flashcards

1
Q

Skeletal Muscle Cellular Organelles

A
  1. Nuclei
  2. Synthetic Machinery
  3. Mitochondria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is an important characteristic regarding the nuclei of skeletal muscle?

A

Multinucleated

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

Location of myonuclei in the muscle?

A

-Dispersed along the inner surface of the plasmalemma, particularly dense in the motor end-plate region

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

Contents of myonuclei

A
  1. Nuclear DNA
  2. RNA (m and t)
  3. Ribosomes
  4. Codons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Components of the Synthetic Machinery

A
  1. Endoplasmic Reticulum
  2. Ribosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Characteristics of the Endoplasmic Reticulum

A
  1. Associated with nucleus
  2. transportation and modification of cellular proteins outside of cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Role of Ribosomes

A

Coordinate protein synthesis

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

Substances associated with mitochondira

A
  1. ATP
  2. NADH
  3. FADH2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Metabolic processes associated with mitochondria

A

Electron Transport Chain

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

Bioenergetic imperative for mitochondria to operate

A

Oxygen (Aerobic)

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

Location of mitochondria within the muscle cell

A

between myofibrils in the z-line region and in relation to nuclei and motor end-plate

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

Unique feature of mitochondria when viewed cross sectionally

A

oval shaped

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

Key structural features of mitochondria

A
  1. Inner and Outer membrane
  2. inner membrane folds called cristae
  3. Matrix between cristate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is housed in the inter-cristae matrix

A
  1. Krebs cycle enzyme
  2. Mitochondrial DNA (mtDNA)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Types of mitochondria

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

Primary location of subsarcolemmal mitochondria

A

Immediately beneath cell membrane (sarcolemma)

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

What is the functional significance of the location of subsarcolemmal mitochondria?

A

They can easily receive arterial oxygen

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

Key difference between Intermyfibrillar and subsarcolemmal type mitochondria?

A

Intermyofibrillar may have higher activity per unit mass

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

Key role of intermyofibrillar mitochondria

A

Maintaining ATP supply for energy transduction during contraction

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

Intermyfibrillar Mitochondria Location

A

Deep within the cell in the contractile elements

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

Cytoplasmic Components

A

ANAEROBIC
1. Soluble Proteins, Cytoskeletal Components
2. Glycogen Granules
3. Glycolytic Enzymes

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

Filamentous Components

A
  1. Myofibrils
  2. Sarcomeres
  3. Myosin Isoforms
  4. Actin
23
Q

Function of Myofibrils

A

Contraction and relaxation

24
Q

Location of myofibrils

A

Separated by mitochondria and sarcoplasmic and transverse tubular system

25
Q

Primary protein filaments found in myofibrils

A
  1. Actin
  2. Myosin
26
Q

How do contractile proteins connect to tendon?

A

Endomysial connective tissue

27
Q

What are the myotendinous attachment proteins?

A
  1. Vinculin
  2. Talin
  3. Paxillin
  4. Tensin
28
Q

A- Bands

A

Anisotropic, dark bands

29
Q

What causes the dark banding of the A band?

A

myosin

30
Q

I bands

A

Isotropic, light bands

31
Q

What causes the light color of the I band?

A

actin

32
Q

Describe the contractile proteins in reseting muscle

A

Actin and myosin overlap

33
Q

H zone

A

pale area
no overlap

34
Q

What causes the dark banding in the M region?

A

filaments cross connecting myosin

34
Q

M region

A

Dark region in the middle of the H zone

35
Q

Describe the structure of the myofilament

A

Each myosin filament surrounded by hexagonal lattice of actin

35
Q

Types of troponin

A
  1. Troponin I (Tnl)
  2. Troponin C (TnC)
  3. Troponin T (TnT)
35
Q

Tropomyosin

A
36
Q

Nebulin

A
37
Q

Myosin Filament Array

A
  1. M lines (M region) Visible
38
Q

Titin

A

Large protein that connects thick myosin filaments to Z disks

39
Q

Role of titin

A

Longitudinal stabilizer for myosin

40
Q

Where does titin bind?

A
  1. thick myosin to z disk
  2. a-actinin to z disk
  3. myomesin in M region
41
Q

What is the role of nebulin in the I band?

A

supports actin and inserts to z disk

42
Q

Primary components of the Z disk

A
  1. a-actinin
  2. desmin
  3. vimentin
  4. Synemin
43
Q

Intermediate filaments

A
  1. Desmin
  2. Vimentin
  3. Synemin
44
Q

Role of the intermediate filaments

A
  1. Transverse connections between Z disks
  2. Keeps myofibrils in order
  3. Attach Z disk to cytoskeleton
45
Q

Membrane Components

A
  1. Sarcoplasmic Reticulum
  2. Transverse Tubules
46
Q

Describe the tubular systems

A

interlacing network within muscle fiber

47
Q

Role of Sarcoplasmic Reticulum

A

Releases Ca2+ into cytosol around myfibril

48
Q

Role of Ca2+ in muscle

A

Binds with TnC, causes contraction

49
Q

Which structure is the site of Ca2+ release?

A

Terminal Cisternae

50
Q

Important Components of the SR membrane

A
  1. Ca2+ release channels (ryanodine receptors)
  2. Ca2+ ATPase (SERCA)
51
Q

What are ryanodine receptors

A

Ca2+ channels