Brainscape's Knowledge GenomeTM

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


See full index

302 > Muscle S9 > Flashcards

Muscle S9 Flashcards

1
Q

muscle primary function

A

transform chemical energy into mechanical energy

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

mechanical energy can produce…

A
  • equilibrium (posture)
  • force (changes in velocity of muscle shortening)
  • work (displacement)
  • transport (circulation and digestion)
  • heat (maintain body temp)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

3 types of muscles

A
  • skeletal
  • cardiac
  • smooth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

smooth muscles are the … to contract and to relax.

A

slowest

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

duration of skeletal muscle twitch

A

shortest, quick

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

duration of cardiac muscle twitch

A

short

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

duration of smooth muscle twitch

A

long

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

skeletal muscle

A

attached to bone by tendon

  • for locomotion and balance
  • voluntary (but also uses reflex)
  • striated
  • multinucleated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

cardiac muscles

A
  • attached to blood vessels only
  • for blood circulation
  • involuntary
  • striated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

smooth muscles

A
  • attached to wall of organs and blood vessels
  • blood pressure control, digestion, bladder control, air flow
  • involuntary
  • NOT striated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

multinucleate skeletal muscle fibre

A

during embryonic development, many myoblasts fuse to form one skeletal muscle fiber

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

muscle fibre can also be referred to as…

A

muscle cell

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

involuntary contractions are under the regulation of…

A

ANS (sympa + para) and endocrine

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

voluntary contractions are under regulation of..

A

somatic nervous system

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

pacemaking capacity

A
  • in smooth and cardio

- capable of generating action potential that can initiate muscle contraction

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

pacemaker activities modulated , but not initiated by…

A

autonomic nervous system

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

Skeletal muscles contract only in response to signal from a..

A

somatic motor neuron

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

No ANS influence on contraction of skeletal muscle EXCEPT…

A

diaphragm for respiration

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

5 properties of muscular tissues

A
  • excitability
  • contractibility
  • extensibility
  • elasticity
  • adaptability
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

excitability

A

-ability to respond to stimuli by production action potentials

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

cardiac and smooth excitability

A

-electrical stimulus initiated by pacemaker cells

22
Q

skeletal muscle cells excitability

A

chemical stimulus that occurs in neuromuscular junction where ACh is released by motor neuron

23
Q

contractibility

A

ability of muscular tissues to contract forcefully when stimulated by action potentials

  • muscle contraction can produce change in velocity of muscle fibre shortening
  • force is produced to generate movement
24
Q

the greater the change in velocity of muscle fibre shortening, the … the contractility

A

created the contractility

25
Q

contraction without muscle shortening =

A

no change in muscle length… TENSION

26
Q

extensibility

A

ability of muscular tissue to stretch without being damaged

27
Q

connective tissue

A

limits range of extensibility and keep it within functional physiological contractile range

28
Q

elasticity

A

ability of muscular tissue to return to its original length and shape after contraction or extension

29
Q

nebulin

A

protein that helps align actin

-lies along the filament, attached to a Z-disk, but does not extend to M line

30
Q

titin

A

protein that provides elasticity and stabilized myosin

-spans distance from one Z disk to M line

31
Q

adaptability

A

normally, there should be no alternation in muscle phenotype
-but muscular tissue has ability to undergo hypertrophy or atrophy (muscle plasticity)

32
Q

properties of skeletal muscle that are shown to have plasticity..

A
  • force of contraction
  • contraction speed
  • endurance
  • oxidative/glycolytic capacity
33
Q

2 main types of muscle fibre in skeletal muscle

A
  • slow twitch oxidative (type I)

- fast twitch oxidative glycolytic (type II)

34
Q

muscle fiber type classification based on..

A
  • speed of contraction
  • resistance to fatigue
  • newer approach based on immunohistochemical labeling of distinct myosin heavy chain isoforms
35
Q

fast twitch oxidative/glycolytic can further be subdivided into…

A

IIa: fast twitch oxidative

IIb/IIx: fast twitch glycolytic

36
Q

muscle fibres belonging to one motor unit are of the same…

A

muscle type

37
Q

each muscle is composed of each … type, with one … the other

A

twitch; dominating

38
Q

type I vs type II area, endurance, and energy efficiency

A

I = small cross-sectional area, high endurance, high energy efficiency

39
Q

slow-twitch oxidative fibres generate …. force

A

weaker; rate of ATP break is slow, velocity of muscle shortening is slow

40
Q

slow-twitch ox fibres require..

A

good supply of oxygen (respiration) and ATP to have high endurance and resistance to fatigue

41
Q

fast-twitch oxidative fibres (IIa) generate … force

A

stronger; rate of ATP break relatively quicker, velocity of muscle shortening is quicker

  • ATP production is also aerobic
  • fatigue resistant, but decreased endurance than type I
  • high density of blood capillaries
42
Q

type I and type IIa are similar with..

A

abundance of myoglobin, but IIa has higher density of mitochondria, and more abundant glycogen content to ensure adequate ATP generation for increased rate of ATP hydrolysis

43
Q

creatine phosphate

A

reservoir for type IIa storage of ATP

-excess ATP during resting state used to synthesize creatine phosphate

44
Q

Creatine + ATP =

A

creatine phosphate + ADP (relaxed muscle)

45
Q

creatine phosphate + ADP =

A

creatine + ATP (energy for contracting muscle)

46
Q

fast-twitch glycolytic fibres gerate … force

A

very strong; ATP break much quicker than the rest, velocity of muscle shortening much faster

  • not capable of sufficient oxidative metabolism to sustain prolong contraction
  • higher glycolytic enzyme activity and creatine phosphate content
  • poor blood capillary supply
  • mainly anaerobic
  • easily fatigued and low in endurance
47
Q

4 main events in excitation-contraction coupling

A
  • ACh released from somatic motor neuron
  • ACh initiated action potential in muscle fibre
  • AP travels along sarcolemma into T-tubules and triggers Ca2+ release from SR
  • Ca2+ binds with TnC and initiates muscle contraction
48
Q

RyR - ryanodine receptor

A

-Ca2+ release channel in SR

49
Q

DHP - dihydropyridine receptor

A

L-type calcium channel in T-tubule

50
Q

To end a contraction…

A

-Ca2+ must be removed from cytosol back to SR thru asarco-endoplasmic reticulum calcium ATPase (SERCA)

51
Q

sliding filament theory

A
  • ATP binds to myosin
  • myosin releases actin
  • myosin hydrolyzes ATP, energy from ATP rotates myosin head to cocked position
  • myosin binds weakly to actin
  • power stroke when tropomyosin moves off binding site
  • myosin releases ADP at end of power stroke

302 (6 decks)

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