Brainscape's Knowledge GenomeTM

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


See full index

Cells to Organisms - Lectures > Lecture 24. Muscle Physiology > Flashcards

Lecture 24. Muscle Physiology Flashcards

1
Q

What is muscle tissue responsible for ?

A

Nearly all types of body movement

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

What do muscle cells consist of ?

A

Filaments of the proteins actins and myosin

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

What are the functions of the filaments of the proteins actin and myosin ?

A

Enable muscles to contract

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

What are the three types of muscle tissue ?

A
  1. Skeletal muscle
  2. Smooth muscle
  3. Cardiac muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is skeletal muscle responsible for ?

A

Voluntary movement

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

What is smooth muscle responsible for ?

A

Involuntary body activities

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

What is cardiac muscle responsible for ?

A

Contraction of the heart

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

What does muscle contraction generate ?

A

Heat

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

What type of tissue is muscle ?

A

Electrically excitable tissue

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

What is muscle activity a response to ?

A

Input from nervous system

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

What does muscle cell contraction rely on ?

A

The interaction between thin actin filaments and thick myosin filaments

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

What does skeletal systems transform muscle contraction into ?

A

Locomotion

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

What does the skeleton provide ?

A

A rigid structure to which muscles attach

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

How are skeletal muscles attached ?

A

In antagonistic pairs

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

What are the actions of antagonistic pairs coordinated by ?

A

The nervous system

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

How do paired muscles work ?

A

Cooperatively

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

What is locomotion ?

A

Movement through space

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

How does skeletal muscle work ?

A

Moves bones and the body

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

How is skeletal muscle characterised ?

A

Hierarchy of smaller and smaller units

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

What does a skeletal muscle consist of ?

A

A bundle of long fibres, each a single cell, running along the length of the muscle

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

What is each muscle fiber ?

A

A bundle of smaller myofibrils arranged longitudinally

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

Why is skeletal muscle called striated muscle ?

A

Because the regular arrangement of myofilament creates a pattern of light and dark bands

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

What is the functional unit of a muscle called ?

A

A saromere

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

What is a sarcomere bordered by ?

A

Z lines

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

Where to thin filaments attach ?

A

Z lines

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

What is the sliding filament model of muscle contraction ?

A

Thin and thick filaments ratchet past each other longitudinally, powered by the myosin muscles

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

What is the structure of myosin ?

A

A long tail region and a globular head region

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

Where does the head of the myosin molecule bind to ?

A

An actin filament

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

What does the head of the myosin molecule binding to an actin filament form ?

A

A cross bridge

30
Q

What does the head of the myosin molecule binding to an actin filament do ?

A

Pull the thin filament towards the centre of the sarcomere-the power stroke

31
Q

What does muscle contraction require ?

A

Repeated cycles of binding and release - cross bridge cycling

32
Q

What is muscle contraction dependent on ?

A

ATP

33
Q

Why does muscle fatigue ?

A

Metabolic reasons: lack of substrate (ATP) or accumulation of metabolites that interere with contraction

34
Q

What generates the ATP needed for muscle contraction ?

A

Glycolysis and aerobic respiration

35
Q

What happens during intense muscle activity ?

A

02 becomes limiting and ATP is generated by lactic acid fermentation

36
Q

Does cardiac muscle fatigue ?

A

No

37
Q

What else is muscle contraction dependent on ?

A

Calcium

38
Q

What binds to actin strands on thin filaments when a muscle fibre is at rest ?

A

The regulatory protein tropomyosin and the troponin complex

39
Q

What prevents myosin and actin interacting ?

A

The regulatory protein tropomyosin and the troponin complex

40
Q

What must happen for a muscle fibre to contract ?

A

Myosin binding sites must be exposed

41
Q

When are myosin binding sites exposed ?

A

When calcium ions bind to troponin complex

42
Q

When does contraction occur ?

A

When the concentration of calcium is high

43
Q

When does muscle contraction stop ?

A

When the calcium ion concentration is low

44
Q

What is the stimulus leading to muscle contraction of a muscle fibre ?

A

An action potential in a motor neuron that makes a synapse with the muscle fibre

45
Q

What does the synaptic terminal of the motor neuron do ?

A

Releases the neurotransmitter acetylcholin

46
Q

What is the function of acetylcholine in skeletal muscle contraction ?

A

Depolarises the muscle causing it to produce and end plate potential

47
Q

Where do action potentials travel ?

A

To the interior of the muscle fibre along transverse tubules

48
Q

What does the traveling of the action potential to the interior of muscle fibres do ?

A

Causes the sarcoplasmic reticulum to release calcium ions

49
Q

Is the contraction of the whole muscle graded ?

A

Yes

50
Q

How does the nervous system produce graded contractions ?

A
  1. Varying the number of fibres that contract

2. Varying the rate at which fibres are stimulated

51
Q

What may each motor neuron synapse with ?

A

Multiple muscle fibres

52
Q

What does a motor unit consist of ?

A

A single motor neuron and all the muscle fibres it controls

53
Q

What is tetanus ?

A

Describes sustained muscle contraction, where a muscle doesn’t relax between contractions

54
Q

What are some examples of disorders related to skeletal muscle ?

A
  1. Amyotrophic lateral sclerosis
  2. Myasthenia gravis
  3. Multiple sclerosis
  4. Duchenne muscular dystrophy
55
Q

How is ALS caused ?

A

Interferes with the excitation of skeletal muscle fibers

56
Q

What is myasthenia gravis ?

A

An autoimmune disease that attack acetylcholine receptors on muscle fibres

57
Q

What is multiple sclerosis ?

A

Demyelinating disease

58
Q

What does cardiac muscle consist of ?

A

Striated cells electrically connected by intercalated disks that contain gap junctions

59
Q

What can cardiac muscle do ?

A

Generate action potentials without neural input

60
Q

Do cardiac muscles have tetanic contraction ?

A

No

61
Q

Where is smooth muscle found ?

A

Mainly in walls of hollow organs such as circulatory system, digestive and reproductive

62
Q

What is slow in smooth muscle ?

A

Contractions - may be initiated by muscles themselves

63
Q

What can contractions be caused by in smooth muscle ?

A

Stimulation from neurons in the autonomic nervous system

64
Q

Why does smooth muscle lack striated ?

A

Actin and myosin are not regularly arrayed

65
Q

How does calcium enter smooth muscle ?

A

They enter the cytosol through smooth muscle

66
Q

What is muscle contraction regulated by in smooth muscle ?

A

Calcium ions

67
Q

How would you build skeletal muscle ?

A
  1. Testosterone

2. Anabolic steroids

68
Q

What is the building of muscle dependent on ?

A

Protein synthesis

69
Q

What does lack of muscle lead to ?

A

Atrophy

70
Q

What can the heart undergo in response to physiological stimulus ?

A

Changes in shape and mass

71
Q

How does endurance training effect the heart ?

A

Increases the volume

72
Q

How does resistance training effect the heart ?

A

Increase in mass

Cells to Organisms - Lectures (36 decks)

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