Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Z OLD Tissues of the Body > Alterations in Skeletal Muscle Function > Flashcards

Alterations in Skeletal Muscle Function Flashcards

1
Q

What are the functions of skeletal muscle?

A

NAME?

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

How can skeletal muscle function be modified?

A
  • Remodelling of muscles
  • Alterations of neuromuscular transmission
  • Muscular dystrophies
  • Other myopathies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can happen to the contractile proteins actin and myosin?

A

They can increase and decrease in nuber

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

When does the remodelling of muscles occur?

A

Continual

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

How long does it take to replace a contractile protein?

A

2 weeks

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

What happens if destruction > replacement?

A

Atrophy

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

What happens if replacement > destruction?

A

Hypertrophy

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

Why does skeletal muscle change with exercise?

A

Metabolic adaptation

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

What happens to skeletal muscle with exercise?

A
  • Sarcoplasmic reticulum swells
  • Increased volume of mitochondria
  • Increased Z band width
  • Increased ATPase
  • Increased density of T tubule systems
  • Increased in no. of contractile protein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Does exercise cause hyperplasia?

A

No

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

Give an example of a high intensity activity?

A

Weight lifting, e.g. 70-90% intensity, short duration, modest frequency

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

What is the effect of high intensity activity?

A

Stimulates contractile protein synthesis, fatter muscle fibres and larger muscles, which increases muscle mass and stength

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

What can high intensity activity lead to?

A

Hypertrophy

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

Give an example of an endurance exercise

A

Jogging e.g. low intensity, for a longer duration, 5 times a week

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

What is the advantage of endurance exercise over high intensity exercise?

A

It increases endurance, but without hypertrophy

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

What does endurance exercise stimulate?

A

Synthesis of mitochondrial proteins and vascular changes

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

What is the result of the stimulation of mitochondrial proteins and vascular changes in endurance exercise?

A

Allows for greater oxygen utilisation

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

What does endurance exercise result in a shift to?

A

Oxidative metabolism of lipids

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

What can lead to disuse atrophy?

A
  • Bed rest
  • Limb immobilisation
  • Sendentry behaviour
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What happens in disuse atrophy?

A

Loss of protein leading to reduced fibre diameter, leading to loss of power

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

At what age does muscle atrophy occur?

A

30+

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

How much muscle mass has been lost my the age of 80?

A

50%

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

What is the loss of muscle mass with ageing called?

A

Sarcopenia

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

What can muscle atrophy with age lead to?

A

Problems with temperature regulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How can muscle atrophy with age lead to hypothermia?
Not enough muscle mass to generate heat themselves
26
What is denervation atrophy known as?
Neurogenic muscular atrophy
27
What are the signs of lower motor neurone legions?
#NAME?
28
How quickly does reinnervation need to occur for recovery from denervation atrophy?
Within 3 months
29
What happens in a muscle with spinal muscular atrophy?
The atrophic fibres are small, angulated and brightly eosinophilic, with an apparent increase in number of nuclei
30
What causes an increase in muscle length?
Sustained stretching
31
What happens when muscles lengthen?
#NAME?
32
What changes of neurology occur in adjustment of muscle length?
- Pain - Stretch response  - Stretch reflex
33
What changes to viscoelastic properties occur in adjustment of muscle length?
Change in connective tissue alignment
34
What reduces the length of muscle?
Immobilisation
35
What are the steps in neuromuscular transmission?
- Opening of presynaptic voltage-dependant calcium channels, causing ACh release - ACh binds to nicotinic receptor  - Binding of ACh to its receptor opens the sodium channel  - Sodium entry depolarises muscle
36
Where are nicotinic receptors located?
On folded end-plate regions
37
What does the depolarisation of muscle following neuromuscular transmission cause?
Release of calcium ions from SR, therefore muscle contraction
38
How is ACh terminated in neuromuscular transmission?
Acetylcholinesterase
39
What happens at high motor neurone firing rates?
ACh release decreases by 25%
40
What needs to be true of ACh receptors?
They must be occupied
41
Give an example of a neuromuscular junction disorder?
Myasthenia Gravis
42
What causes Myasthenia Gravis?
Autoimmune destruction of the end patch ACh receptors (IgA antibodies to AChRs)
43
What is the result of the autoimmune destruction in Myasthenia Gravis?
#NAME?
44
What are the symptoms of Myasthenia Gravis?
- Fatiguability  - Sudden falling - Ptosis - Double vision  - Effected by general state of health, e.g. fatigue and emotion
45
What causes the fatiguability and sudden falling in Myasthenia Gravis?
Sudden ACh release
46
What is ptosis?
Drooping upper eyelids
47
How to the symptoms of Myasthenia Gravis change over time?
They fluctuate
48
What is the treatment for Myasthenia Gravis?
- Acetylcholinesterase inhibitors - Immune suppressants - Plasmapheresis  - Thyrectomy
49
What does plasmapheresis do?
Remove harmful antibodies from patients serum
50
Give 2 toxins that inhibit neuronal Na + channel
- Tetrodotoxin  - Saxitoxin
51
What toxin inhibits Ca 2+  channel?
α-Conotoxin
52
What toxin inhibits K +  channel?
Dendrotoxin
53
Give 2 toxins that inhibit ACh release?
#NAME?
54
Give 2 toxins that inhibit acetylcholinesterase
- Physostigmine  - DFP
55
Give 3 toxins that inhibit the muscle Na +  channel
- Tetrodotoxin - Saxitoxin - µ-Conotoxin
56
Give 2 toxins that stimulate AChR channel?
- Acetylcholine  - Nicotine
57
Give 2 toxins that inhibit the AChR channel?
- d-Tubocurarine  - α-Bungarotoxin
58
What are the two main causes of muscular dystrophies?
#NAME?
59
Give 8 types of muscular dystrophy
- Duchenne type  - Becker type  - Emery-Dreifus  - Limb gurdle - Facioscapulohumeral  - Distal - Occulopharyngeal  - Congenital Mersonin Deficiency
60
Where does Duchenne and Becker type muscular dystrophy affect?
- Upper legs - Calves - Neck - Shoulders - Upper arms  - Pectoral
61
What causes Duchenne type muscular dystrophy?
Complete absence of dystrophin
62
What causes Becker type muscular dystrophy?
Altered truncated dystrophin
63
Where does Emery-Dreifus muscular dystrophy affect?
#NAME?
64
Where does limb gurdle muscular dystrophy affect?
- Upper arms - Shoulders - Pectoral  - Upper legs
65
What causes limb gurdle muscular dystrophy?
Deficiency of sarcoglycans
66
Where does facioscapulohumeral muscular dystrophy affect?
#NAME?
67
Where does distal muscular dystrophy affect?
#NAME?
68
Where does occulopharyngeal muscular dystrophy affect?
#NAME?
69
What causes Congenital Mersonin Deficiency?
50% deficiency of merosin
70
What are the consequences of protein abnormality?
- Muscle fibres tear themselves apart on contraction - Enzyme creatine (phospho)kinase liberated into serum - Calcium enters cell causing cell death - Pseudohypertrophy (swelling), before fat and connective tissue replace muscle fibres
71
When does Duchenne muscular dystrophy first become apparent?
Early onset
72
What is the sign of Duchenne muscular dystrophy?
Gower’s sign
73
What is Gower’s sign?
Pushing on knees to give power
74
What is meant by contractures?
Imbalance between agonist and antagonistic muscles
75
How is Duchenne muscular dystrophy treated?
Steroid therapies
76
What is being done to help with Duchenne muscular dystrophies?
Genetic research, e.g. into gene therapy, stem cells etc
77
What can skeletal muscle disorders be caused by?
- Denervation  - Myopathies
78
What is the root of denervation disorders?
Neurological causes
79
What are myopathies?
Primary muscle diseases
80
Give 5 types of myopathies
- Inflammatory - Electrolyte imbalances - Thyrotoxicosis - Hypoparathyroidism  - Channelopathies
81
Give 3 examples of inflammatory myopathies
- Polymyositis  - Myalgia  - Influenza
82
Give an example of a myopathy caused by an electrolyte imbalance?
Cramps
83
What can the result of thyrotoxicosis be?
Increased basal metabolic rate and protein catabolism
84
Give an example of a channelopathy
Malignant hyperthermia

Z OLD Tissues of the Body (19 decks)

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