Brainscape's Knowledge GenomeTM

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


See full index

Body Logistics > Muscle Tissue > Flashcards

Muscle Tissue Flashcards

1
Q

What are the two categories of muscle?
Categorise the three types of muscle

A

Striated - cardiac and skeletal

Non-striated - smooth

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

What causes striations?

A

Repeating bands of the proteins actin and myosin
Present along the length of the myofibrils

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

For each type of muscle state:
- whether myoglobin is present
- type of control
- type of nerve-muscle communication

A

S - present, voluntary, direct

C - present, involuntary, indirect

M - absent, involuntary, indirect

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

What type of molecule is myoglobin?
What does it supply? To what?

A

Red protein

O2 to working striated muscles

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

What condition particularly does haemoglobin give O2 to myoglobin?

A

Low pH

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

When striated muscle dies or is damaged what happens?
What can this lead to?

A

Myoglobin is released into the bloodstream

Renal damage

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

What removes myoglobin from the blood?
What clinical observation does this lead to?

A

Kidneys

Tea-coloured urine

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

What is the outer membrane of a muscle cell called?

A

Sarcolemma

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

What is the cytoplasm of a muscle cell called?

A

Sarcoplasm

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

What is a sarcomere?

A

The contraction unit in a striated muscle

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

What are the thick and thin myofilaments?

A

Thin - actin

Thick - myosin

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

What is the epimysium?

A

Dense fibrous connective tissue surrounding muscle tissue

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

What are the sections of muscle tissue called?

A

Fascicles

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

What type of connective tissue surround fascicles?

A

Perimysium

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

What type of loose tissue surrounds muscle fibres?

A

Endomysium

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

What is underneath the endomysium?

A

Sarcolemma

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

What are the sections in a fascicle called?

A

Muscle fibres

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

What are the sections in a muscle fibre called?

A

Myofibril

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

What is the main function of skeletal muscle?

A

Contraction

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

What direction is movement?

A

Along the direction of a fascicle

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

What is created at the origin and insertion point?
Are they proximal or distal?
Give a rough example of each

A

Origin - tension, proximal
Shoulder

Insertion - movement, distal
Elbow

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

What do distal and proximal mean?

A

Distal - further away from the centre

(Proximal is the opposite)

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

What does the perimysium contain? (2)

A

Capillaries and nerves

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

What do skeletal muscle have a lot of - that you can look for in pictures

A

Mitochondria - dark

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

Why don’t Z lines line up in some pictures?

A

When the cell is activated
The middle section contracts first

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

What are the three types of muscle contraction speeds?

A

Slow
Fast
Intermediate

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

What are the two types of twitch fibres?
What colour are they?

A

Slow - red
Fast - white

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

What two things is continued muscle contraction dependent on?

A

Ca2+

ATP

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

What do cardiac muscles specifically have?

A

Intercalated discs

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

What types of granule do cardiac muscles have?
What are they released by?
When are they released?

A

ANP - atria

BNP - ventricles

Heart failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How do you reduce arterial pressure? (2)

A

Decrease blood volume
Decrease systemic vascular resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is hypertrophy?

A

Enlargement of individual cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is hyperplasia?

A

Multiplication of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are three key features of purkinje fibres?

A
  • abundant glycogen
  • sparse myofibrils
  • extensive gap junctions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Describe the function of purkinje fibres

A
  • rapidly conduct action potentials
  • enabling ventricles to contract in a synchronous manner
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Where are nuclei in cardiac muscle?

A

Central

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Where are nuclei in skeletal muscle

A

Peripheral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Describe the nucleus in smooth muscle cells

A

Single large central

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What three things do smooth muscle cells not have?

A

Striations
Sarcomeres
T tubules

40
Q

How does smooth muscle contraction compare with skeletal and cardiac? (3)

A
  • slower
  • more sustained
  • requires less ATP
41
Q

How do skeletal muscle repair?

A
  • they cannot divide
  • regenerate by mitotic activity of satellite cells (hyperplasia)
  • satellite cells can fuse with existing muscle cells (hypertrophy)
42
Q

What cells are responsible for repair in skeletal muscle?

A

Satellite

43
Q

What type of muscle is incapable of repair?
What happens instead?

A

Cardiac

Fibroblasts invade and divide
Laying down scar tissue

44
Q

How do smooth muscle repair?

A
  • they retain their mitotic activity
45
Q

What is the central line in a myofibril?
What does it not have?

A

M line

Myosin heads

46
Q

What is the zigzagged line in a myofibril?

A

The z line

47
Q

What does an A band include?

A

End to end of myosin

48
Q

What is the light band in a myofibril?

A

I

49
Q

What is the dark band in a myofibril?

A

A

50
Q

What does the H band include?

A

The M line, not including the myosin

51
Q

In white and red muscle compare:
Amount of myoglobin and mitochondria
Fibre diameter
Amount of cytochrome

A

White - lower
White - larger
White - lower

52
Q

How do myocytes communicate in cardiac and smooth muscle?

A

Through ago junctions

53
Q

Name two types of myofilaments

A

Actin and myosin

54
Q

Describe the general structure of myosin

A

Two heads
Protrude at opposite ends

55
Q

What are the two protein components of actin?

A

F actin fibres
G actin globules

56
Q

What two molecules are associated with actin?
Describe them

A

Troponin - attach to each tropomyosin molecule

Tropomyosin - coil around the actin helix - reinforcing it

57
Q

Describe how components of myofibrils change shape Erin contraction

A
  • actin and myosin remain the same
  • Sarcomeres shorten
  • z lines come close together
58
Q

What does the innveration of muscles mean?

A

A single motor neurone is able to innveration multiple muscle fibres
Causing fibres to contract at the same time

59
Q

In neuromuscular junction transmission what is released into the synaptic cleft?

A

Ach

60
Q

What does Ach bind to?
What does this cause?
What does this cause?

A

Ach receptors

Depolarisation of sarcolemma

Ca2+ released from gated Ca2+ ion release channels, into the sarcoplasm

61
Q

What does Ca2+ bind to?
What does this lead to?

A

TnC subunit of troponin

Tropomyosin dissociates from troponin

62
Q

Where do are Ca2+ returned to at the end?

A

Terminal cisternae of sarcoplasmic reticulum

63
Q

What causes myasthenia gravis?

A
  1. Antibodies directed against Ach receptor
  2. Blocking the receptor
  3. Reduction in receptor number
  4. Reduced synaptic transmission
64
Q

Symptoms of myasthenia gravis

A

Ptosis - drooping of one eyelid
Slurred speech
Difficulty holding head up
Choking on food

65
Q

What are the five steps of the sliding filament theory?

A
  1. Myosin head forms a cross bridge with the actin filament
  2. The head pulls on the actin filament through a form of relaxation (passive)
  3. ATP attaches to the myosin head - breaking the bond with the actin filament
  4. ATP hydrolyses and cocks the myosin head back to the starting point (active)
  5. The myosin filaments slide along the actin - causing the band to shrink
66
Q

Describe botulism toxin and Botox?

A
  • clostridium botulinum produces botulism toxin
  • it blocks neurotransmitter release at motor end plate
  • skeletal muscles are in a non-contractile state
67
Q

What is the botulism toxin used for?

A
  • treat muscle spasms
  • treat wrinkles
68
Q

Describe organophosphate poisoning

A
  • it inhibits function of Ach esterase
  • Ach cavities at neuromuscular junction is increased
69
Q

Name some symptoms of organophosphate poisoning

A
  • Salivation
  • muscle cramps
  • urination
70
Q

What type of mutation is duchenne muscular dystrophy?

A

C linked recessive of dystrophin gene

71
Q

What causes duchenne muscular dystrophy?

A
  1. Absence of dystrophin
  2. Excess Ca2+ enters muscle cells
  3. Ca2+ taken up by mitochondria
  4. Water taken up into mitochondria
  5. Mitochondria and muscle cells burst
  6. Creatine kinase and myoglobin levels are high in the blood
  7. Muscle cells replaced by adipose tissue
72
Q

What would show in a blood test for people with duchenne muscular dystrophy?

A

Creatine kinase
Myoglobin

73
Q

What are some symptoms of duchenne muscular dystrophy?

A
  • poor balance
  • belly sticks out
  • tight heel cord
  • arms and shoulder back when moving
74
Q

What is an agonist?

A

Primer movers (main muscle for a movement)

75
Q

What is an antagonist?

A

Oppose agonists

76
Q

What is a synergist?

A

The assist agonists

77
Q

What is a neutraliser?

A

Prevent unwanted action that an agonist can perform

78
Q

What is a fixator?

A

Act to hold a body part immobile whilst another part is moving

79
Q

What is a first class lever?

A

Effort at one end
Load at the other

Fulcrum in middle

80
Q

What is a second class lever?

A

Effort at one end
Fulcrum at other

Load in middle

81
Q

What is a third class lever?

A

Load at one end
Fulcrum at other

Effort in middle

82
Q

How are muscles organised?
Surrounded by what?

A

Grouped into compartments with similar actions

Thick dense fascia

83
Q

What causes compartment syndrome?

A
  1. Trauma in one compartment
  2. Internal bleeding
  3. Exerts pressure on blood vessels and nerves
84
Q

Name some symptoms of compartment syndrome

A
  • deep poorly localised pain
  • paresthesia (pins and needles)
  • swollen shiny skin
85
Q

How is compartment syndrome treated?

A

Fasciotomy

Covered by skin graft

86
Q

Define muscle tone

A

The tension in a muscle at rest

87
Q

Define muscle strength

A

The muscles ability to contract and create force in response to resistance

88
Q

What is muscle tone regulated by?

A
  • gravity
  • use
  • muscle elasticity
  • motor neuron acitvity
89
Q

Muscles retain tension and stiffness
What does this cause?

A
  • muscles ready to react
  • never fully relaxed
  • improves with exercise
90
Q

What causes atrophy?
Define it simply

A

The destruction is more than replacement:
- disuse
- surgery
- disease

Muscles wasting away

91
Q

What is the opposite of atrophy?
What is the mechanism?

A

Hypertrophy

  1. New muscle fibrils produced
  2. New Sarcomeres added in the middle of existing ones
  3. New muscles fibres arise from mesenchymal cells
92
Q

What is used to diagnose heart attacks?
What is used now?

A

Creatine kinase levels in blood

Troponin I assay

93
Q

What leads to a rise in plasma creatine kinase levels?

A
  • intramuscular injection
  • vigorous physical exercise
  • a fall
  • acute kidney injury
94
Q

How is troponin assay used as a marker for myocardial infarction?
What must you note?

A
  • released from ischaemic cardiac muscle

(Not necessarily proportional to degree of muscle damage)

95
Q

What causes malignant hyperthermia? (2)

A
  • Severe reaction to certain drugs used for anaesthesia
  • massive contractile fasciculation (involuntary movement)

Body Logistics (9 decks)

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