Brainscape's Knowledge GenomeTM

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


See full index

PHYS: UNIT 2 > Muscular System > Flashcards

Muscular System Flashcards

1
Q

3 types

A

Skeletal, Smooth, Cardiac

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

Striations are in _____ muscle

A

Skeletal and Cardiac

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

Intercalated disks are in the _______ muscle

A

Cardiac

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

Skeletal muscle fiber traits

A

Multinucleated, mitochondria, transverse(t) tubules

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

Sarcolemma

A

Plasma membrane in skeletal muscle

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

Sarcoplasm

A

Cytoplasm in skeletal muscle

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

Smooth e.r in skeletal muscle

A

Sarcoplasm reticulum

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

T tubules

A

Channels made up of membrane that send action potential from sarcolemma to Sarcoplasm reticulum

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

Traits of skeletal muscle

A

Sarcomeres, myofibrils, striations

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

Sarcomeres

A

Form myofibril, smallest contractile unit of muscle

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

Myofibrils

A

Contractile organelles, cause striations

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

Striations

A

Caused by myofibrils, thick and thin filaments

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

Contraction

A

Activation of force generating sites within muscle fibers (cross bridges)

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

Motor unit

A

Motor neuron and skeletal muscle fibers it innervates

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

Steps of muscle contraction

A
  1. ATP binds to myosin head
  2. ATP broken down into ATP+ phosphate
  3. Myosin head extends and binds to actin filament
  4. ADP and phosphate detach from myosin head
  5. M.H returns to compact formation and pulls actin filament as it does
  6. Myosin head detaches from actin filament when ATP binds again
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Cardiac Muscle

A

Striated, use sliding filament method to contract
1-2 central nuclei
Branched w intercalated disks
Desmosomes and gap junctions
Absolute refractory period is 250 milli, prevent tetanic contractions

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

Nodal cells

A

Stimulate own action potentials in the heart (automaticity) for the heart

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

Single unit smooth muscle

A

Respond to stimuli as single unit bc cells are connected by gap junctions

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

Multi unit smooth muscle

A

Respond to stimuli independently, few gap junctions

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

Response (excitatory or inhibitory) depends on ________________

A

Receptors the chemical receptors bind to and what mechanism they activate

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

A single motor neuron connects to _______ muscle fiber

A

Many

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

Each muscle fiber is connected to more than one motor neuron.

A

False

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

When an action potential occurs in a _______ all the _________ contract

A

Motor neuron, muscle fibers (the muscle fibers are the h*es that copy)

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

There’s are many motor units within a muscle

A

True

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

Skeletal muscle are only activated by action potentials from neurons.

A

True

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

Alpha motor neurons

A

Neurons whose axons activate skeletal muscle fibers

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

Where are the cell bodies of (alpha) motor neurons located?

A

Brain stem and spinal cord

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

The axons of the motor neurons are ________ to allow ________

A

Myelinated, signals to travel fast

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

Neuromuscular junction

A

Junction between axon terminal and muscle cell, transport vesicles with acetylcholine

30
Q

Events at N.M junction

A

Action potential flys down axon, voltage gated calcium channel open and calcium rushes into cell, The change in potential releases ACh from terminals into NMJ, ACh binds to receptors on muscle cells, Sodium channels open, sodium rushes into cell, change in potential causes muscle cell to depolarize, action potential started in muscle cell, down the m. Fiber, excess acetylcholine in NMJ is broken down to prevent over excitation

31
Q

All neuromuscular junctions are ______

A

Excitatory

32
Q

Acetylcholineesterase

A

Enzyme that breaks down ACh

33
Q

Botulinum toxin (Cosmetic BOTOX)

A

Potent poison that blocks the release of ACh from axon terminals (disrupts proteins necessary for ACh vesicles to bind)

34
Q

What makes up a Sarcomeres?

A

Skeletal muscle made up of actin and myosin filaments

35
Q

Protein composition of thin filaments

A

Actin, troponin, tropomyosin that regulate contraction

36
Q

Each actin molecule contains…

A

A binding site for myosin

37
Q

Tropomyosin

A

Rod shaped
Two intertwined polypeptides
Held in position by troponin

38
Q

Troponin

A

Holds tropomyosin down to actin
When calcium binds to troponin, it releases and allows tropomyosin to binds to actin

39
Q

Sliding Filament Mechanism

A

Force causes shortening of muscle, overlapping thick and thin filaments in each Sarcomeres move past each other, propelled by movement of cross bridges

40
Q

Shortening of Sarcomeres causes shortening of filaments

A

False; it changes the amount of overlap

41
Q

Single Fiber Contraction

A

Muscle tension, load, twitch

42
Q

Muscle tension

A

Forces exerted on object by contracting muscle

43
Q

Load

A

Force exerted on muscle by object

44
Q

Twitch

A

Mechanical response of muscle fiber to a single action potential

45
Q

Isometric Twitch

A

Length of muscle stays the same of tension changes

46
Q

Isotonic Twitch

A

Tension stays the same but muscle length changes

47
Q

Summation

A

Increase in muscle tension from successive action

48
Q

Tetanus

A

Maintained contraction in response to repetitive simulation

49
Q

Titin

A

Protein responsible for passive elastic properties of relaxed muscle fibers (stetching increases passive tension)

50
Q

Muscle fatigue

A

Decline in muscle tension as result of previous contractile activity, (slower rate of relaxation and ⬇️ shortening velocity)

51
Q

Acute fatigue from excessive involves

A

⬇️ ATP concentration, ⬆️in ADP, Pi, Mg, H and O2 free radicals

52
Q

Types of skeletal muscle fibers

A

Oxidative and glycolytic, slow and fast

53
Q

Oxidation skeletal fibers

A

Numerous mitochondria for E, long term contraction

54
Q

Glycolytic skeletal fibers

A

Few mitochondria but lots of glycolytic enzymes and stores, produce E quickly

55
Q

Type 1 Skeletal Fibers

A

Slow oxidative, combine low myosin - ATPase activity w high oxidative capacity
Rate of fatigue: slow
Small fiber diameter

56
Q

Type 2A Skeletal Fibers

A

Rate of fatigue: intermediate

57
Q

Type 2X Skeletal Fibers

A

Rate of fatigue: Fast

58
Q

Each muscle fiber only contains one of each fiber

A

False; it contains a mixture of all

59
Q

Tension a muscle can develop depends on…

A

Amt of tension developed from each fiber, number of fibers contracting at once

60
Q

Motor Unit Size Varies

A

Small motor units are in small intricate places

61
Q

Shortening velocity…

A
62
Q

M. Adaptation to Excersize

A

Increase size of muscle fibers (hypertrophy)
Changes capacity for ATP production
Changes myosin they express
USE IT OR LOSE IT

63
Q

Disuse atrophy

A

Arm in a cast

64
Q

Denervation Atrophu

A

Nerve damage = loss of function

65
Q

Muscle cramps

A

Involuntary tetanic contraction of skeletal muscle
A.P fire are highhh rates
Caused by electrolyte imbalance in extra cellular fluid (persistent dehydration or over excersize

66
Q

Smooth muscle fibers are ______ than skeletal muscles

A

Smaller

67
Q

Smooth muscle cells

A

Single nucleus
Divide throughout life
DO NOT have troponin
DO NOT have Sarcomeres (no banding pattern, hence smooth)

68
Q

Smooth muscle contraction occurs by…

A

Sliding filament mechanism

69
Q

Pacemaker Potential

A
70
Q

Varicosities

A

PHYS: UNIT 2 (4 decks)

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