Brainscape's Knowledge GenomeTM

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


See full index

Block 5 ellen > Muscle physiology L13 > Flashcards

Muscle physiology L13 Flashcards

1
Q

What are muscle stem cells called

A

satellite cells

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

When do satellite cells become activated

A

growth and muscle repair

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

Outer layer of muscle fascia

A

epimysium

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

What does the perimysium surround

A

the muscle fascicle

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

what surrounds the muscle fiber

A

endomysium

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

What are individual muscle fibres called

A

myofibrils

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

What surrounds myofibrils

A

sarcolemma membrane

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

A sacromere is between

A

2 Z lines

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

Difference between cardiac and skeletal muscle

A

cardiac= branched

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

What causes striations

A

overlap of actin and myosin

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

thick filament=

A

myosin

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

thin filament=

A

actin

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

2 proteins associated with actin

A

tropomyosin

troponin complex

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

troponin complex is made of

A

TnT
TnC
Tnl

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

What decreases during muscle contraction

A

distance between the Z lines

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

Calcium binds to

A

troponin C

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

What moves out of the myosin binding site

A

TnI

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

What does the myosin head act as

A

ATPase (hydrolysing ATP)

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

What is optimal resting length for a muscle

A

full overlap between thick and thin filaments

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

Decreased muscle length

A

Actin poking through M line; myosin bumping into Z disc

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

increased muscle length

A

decreased overlap

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

No overlap of myosin and actin?

A

Muscles are not naturally stretched to this point

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

Rigor mortis begins

A

3-4 hours after death

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

HOW LONG DOES RIGOR MORTIS LAST FOR

A

24 hours

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

Why does rigor mortis happen

A

Ca2+ diffuses out of SR and allows myosin to bind to actin, no ATP to detach cross bridges

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

What stops rigor mortis

A

proteolytic lysosomal enzymes decompose cells

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

3 things neuromuscular junction consists of

A

axonal terminal of a somatic motor neuron
synaptic cleft
Motor end plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Why are muscle membranes highly folded

A

increase surface area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Neurotransmitters in skeletal muscle=

A

acetyl choline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Receptors in skeletal muscle=

A

nicotinic cholinergic receptors

31
Q

In a neuromuscular junction what channels are opened on the motor end plate

A

Na/K+ channels (more sodium goes in )

32
Q

Choline —>

A

retaken up by the nerve terminal

33
Q

Acetate—>

A

goes into kreb cycle

34
Q

What does curare do

A

blocks nicotinic acetylcholine receptors

35
Q

What does botulinum toxin do

A

stops the release of the vesicles

36
Q

Resting membrane potential of skeletal muscle=

A

-90mV

37
Q

Threshold of skeletal muscle=

A

-50mV

38
Q

What does suxamethonium do

A

depolarises the muscle membrane preventing end plate potentials

39
Q

In skeletal muscle what is either side of the transverse tubule

A

terminal cisternae

40
Q

A triad in skeletal muscle=

A

2 terminal cisternae either side of transverse tubule

41
Q

What happens within the triad

A

excitation-contraction coupling

42
Q

In cardiac muscle what is instead of a triad

A

a diad

43
Q

why are L-type Ca2+ channels opened

A

membrane depolarisation (DHP binds to the channel)

44
Q

What binds to the Ca2+ release channels

A

Ryanodine

45
Q

What causes the release of Ca2+ from the SR

A

mechanical coupling between the L-type Ca2+ and the Ca2+ release channel

46
Q

In skeletal muscle what isn’t released compared with cardiac

A

extracellular calcium

47
Q

What pumps calcium back into the Sarcoplasmic reticulum

A

Calcium ATPase

48
Q

What is a muscle twitch

A

muscle contraction in response to a stimulus that causes action potential in one or more muscle fibres

49
Q

Three phases of muscle twitch

A

Lag phase
Contraction phase
Relaxation phases

50
Q

What is temporal summation

A

before the muscle has relaxed from contraction it is stimulated again
Increase in contraction strength

51
Q

what is unfused tetanus

A

stimulations very close together only a small amount of relaxation

52
Q

What is fused tetanus

A

muscle stimulated so much no time for relaxation

53
Q

What is a motor unit

A

Motor nerve + all muscle fibres it innervates

54
Q

innervation ratio=

A

the number of muscle fibres innervated by a nerve

55
Q

In a small stimulation what motor neurons are recruited first

A

small motor neurons innervating small muscle fibres

56
Q

In a large stimulus what motor neurons are recruited

A

larger motor neurons and there motor units

57
Q

isometric muscle contraction=

A

no change in muscle length

58
Q

isotonic muscle contraction=

A

length shortens

59
Q

As the force of a load increases contraction changes from

A

isotonic–> isometeric

60
Q

3 types of skeletal muscle

A 
slow-twitch (type 1)
Fast-twitch (type 2b)
Fast twitch (type 2a)
61
Q

Facts about slow twitch type 1 (4)

A

always oxidative
resistant to fatigue
most myoglobin (red fibres)
Good blood supply

62
Q

Which fibres have the most myoglobin

A

slow twitch type 1

63
Q

What do slow twitch fibres control

A

posture

64
Q

Fast twitch type 2b (3) facts

A

white fibres
poorer blood supply
susceptible to fatigue

65
Q

Fast- twitch 2a facts

A

intermediate fibres
oxidative
intermediate myoglobin (pink-red)
Resistant to fatigue

66
Q

2 types of muscle fibres resistant to fatigue

A

slow twitch

fast twitch 2a

67
Q

3 sources of ATP in muscles

A

creatine
anaerobic respiration
aerobic respiration

68
Q

Myopathy=

A

any muscle disease

69
Q

Myositis =

A

muscle inflammatory

70
Q

Muscular dystrophy is

A

weakening skeletal muscle over time (inherited)

71
Q

Myasthenia=

A

increasing weakness on exercise

72
Q

Myotonia=

A

failure of relaxation

73
Q

Channalopathies=

A

abnormal Na+, K+, CL- channels

Block 5 ellen (17 decks)

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