Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Physiology 502 > Muscles > Flashcards

Muscles Flashcards

1
Q

Skeletal muscle function

A

Movement, support, heat production

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

Muscle components

A

Myofilament - muscle fiber - fascicle - muscle

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

Outer surface of muscle

A

Endomysium, perimysium, epimysium

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

Muscle fiber characteristics

A

Multinucleated, post-mitotic

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

Actin

A

Associated with tropomyosin and troponin

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

Troponin

A

A - actin
C - calcium
T - tropomyosin

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

Tropomyosin

A

Block myosin binding site on actin

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

Myosin

A

Motor, 2 heads bind to actin & ATP

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

Titin

A

Spring, maintains myosin & sarcomere

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

Nebulin

A

Maintains actin

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

Desmin

A

Anchors to ECM

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

Dystrophin

A

Packages myofibrils

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

Transmission of force

A

Longitudinal @ myotendinous junctions
Lateral @ network of muscle fibers

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

Defect in dystrophin

A

Duchenne’s muscular dystrophy

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

Sliding filament moodel

A

Sarcomere shortens
Filaments slide on each other but don’t shorten

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

Cross bridge cycling initiation

A

@ rest, cb energized by ATP going to ADP + Pi = strained
Ca enters and binds troponin, tropomyosin moved from actin

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

Cross bridge cycling steps

A
  1. cross bridge attaches to actin
  2. power stroke, Pi released, actin moves, ADP released
    rigor - myosin bound to actin
  3. new ATP binds myosin, myosin released actin
  4. reenergized when ATP splits
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Termination of cross bridge cycling

A

No action potential, no calcium released, actin is blockede

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

Neuromuscular junction

A

Muscle fiber innervated by 1 motor neuron
ACh released

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

Recruitment

A

More motor units, more force

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

Propogation

A
  1. Action potential depolarizes membrane
  2. Calcium channels open and calcium enters
  3. Ca activated ACh vesicles
  4. ACh released and binds to nicotinic ACh-R @ motor end plated
  5. Sodium enters causing EPP
  6. Depolarization and action potential
  7. Action potential propagates down membrane, into T-tubules
  8. DHP-R in T-tubules activated
  9. RyR activated
  10. More calcium release and cross bridge cycling begins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Excitation-contraction coupling

A

Calcium is essential
DHP-R sense depolarization, activated RyR, calcium released from SR

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

Tension & Load

A

tension moves load

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

Isotonic contraction

A

Change in muscle length, can be eccentric or concentric

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

Concentric contraction

A

Muscle shortens, force > load

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

Eccentric contraction

A

Muscle lengthens, force < load
Can disrupt sarcomere

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

Isometric contraction

A

No change in muscle length

28
Q

Muscle twitch

A

1 action potential, latency between act pot and twitch

29
Q

Contraction time

A

Depends on fiber type

30
Q

Heavier load

A

Increased latency, decreased velocity, duration and distance

31
Q

Summation

A

Successive action potential

32
Q

Unfused tetanus

A

Oscillate between partial relaxation and contraction

33
Q

Fused tetanus

A

Maximum tensions

34
Q

Power

A

load x velocity

35
Q

Muscle metabolism

A

Depends on ATP production

36
Q

Formation of ATP

A

Phosphorylation of ADP by creatinine
Phosphorylation of glycolytic pathway
Oxidative phosphorylation

37
Q

Glycolytic

A

Fast, inefficient
Anerobic

38
Q

Oxidative phosphorylation

A

Slow, efficient
Aerobic

39
Q

Fast glycolytic fibers (2B)

A

Fatigue quick, larger, stronger

40
Q

Fast oxidative fibers (2A)

A

Intermediate

41
Q

Slow oxidative (1)

A

Don’t fatigue quick, smaller, weaker

42
Q

Muscle fatigue

A

Decreased tension and velocity

43
Q

Excitation-contraction coupling failure

A

No depolarization

44
Q

Lactic acid build up

A

Excess H+, inhibits Ca-ATPase

45
Q

Inhibition of cross bridge cycling

46
Q

Central command fatigue

A

Brain related i.e. motivation

47
Q

Whole muscle contraction

A

Depends on fibers (type and #), action potential frequency, length, diameter, fatigue, motor units

48
Q

One motor unit

A

ALWAYS same types of fibers

49
Q

Slow motor unit

A

Long twitch, lo force and lo fatigue
Slow oxidative, recruited first
Preserved for postural

50
Q

Fast motor unit

A

Short twitch, hi force, hi fatigue
Fast glycolytic

51
Q

Strength training

A

Hypertrophy, increased force, more sarcomeres in parallel

52
Q

Endurance training

A

Little hypertrophy

53
Q

Atrophy

A

Decreased diameter, decreased sarcomeres
Fast fibers lost first

54
Q

Myogenesis

A
  1. Induction
  2. Migration
  3. Aggregation
  4. Proliferation
  5. Differentiation
55
Q

Repair

A

Satellite cells divide asymmetrically

56
Q

Myostatin

A

Knockout leads to early hypertrophy

57
Q

Types of atrophy

A

Disuse
Denervation
Microgravity

58
Q

Aging

A

Decreased motor units and reinnervation

59
Q

Smooth muscle characteristics

A

Unstriated, spindle cell, one nucleus, involuntary
No sarcomeres
No troponin or tropomyosin

60
Q

Smooth muscle structure

A

Anchored to plasma membrane, connected by adherence junctions

61
Q

Smooth muscle signaling

A

Travels thru gap junctions, slow ATP use, no fatigue

62
Q

Smooth muscle contraction

A

Myosin light chain kinase activates and phosphorylates myosin
Use caveolae
Extracellular calcium and SR calcium
Calcium plays active role

63
Q

Latch state

A

Continuous tension in smooth muscle

64
Q

Basal state

A

Smooth muscle tone

Physiology 502 (4 decks)

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