Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BDS1 > Muscle > Flashcards

Muscle Flashcards

1
Q

What are the 4 tissue types?

A

Epithelial, connective, nervous, muscle

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

What are the 3 types of muscle?

A

Skeletal, cardiac, smooth

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

Function of skeletal muscle

A

contract to produce movement of skeleton (attached to bone)

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

Function of cardiac muscle

A

Movement/Pumping of blood through cardiovascular system

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

Function of smooth muscle

A

movement of substance through visceral, hollow organs

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

What are the 3 ways of classifying muscle?

A
  • by the way it is controlled whether it is the somatic (voluntary) or autonomic (involuntary) NS
  • structure (striated or not)
  • Muscle type - cardiac, skeletal, smooth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When can skeletal muscle contraction be subconscious?

A

For maintaining posture/balance

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

What is an alternative name for skeletal muscle cells?

A

Fibres

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

Structure of muscle fibres

A

elongated, cylindrical, multinucleated cells containing myofibrils made of repeating units of myofilaments

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

Where are the nuclei located in a muscle fibre?

A

Around peripheral edge (no space else where)

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

Why is an individual skeletal muscle an organ?

A

Composed of multiple tissue types. Mainly skeletal muscle tissue but also nervous tissue, blood vessels, connective tissues.

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

What is the name of the dense irregular connective tissue encasing each muscle?

A

Epimysium

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

Function of the epimysium

A

Separates muscle from other tissues and organs

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

How is muscle tissue arranged?

A

Arranged into bundles (fascicles) of muscle fibres

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

What is the name of a bundle in skeletal muscle?

A

Fascicle (pl. fasciculi)

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

What is the perimysium?

A

Loose connective tissue that encases each fascicle

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

What is the name of the loose connective tissue that encases each muscle fibre?

A

Endomysium

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

Function of endomysium

A

Separates individual muscle fibres from their neighbours

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

Function of tendon

A

Helps to transfer the force of the muscle contraction to bone

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

What is a tendon formed from?

A

The epimysium, perimysium and endomysium come together at the tapered end of a muscle to form a tendon. Gives a very strong attachment to bone

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

Where do blood vessels and nerves exist in skeletal muscle?

A

Spread through connective tissue (epimysium, perimysium, endomysium). Each muscle fibre has its own blood supply.

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

What feature gives the striated appearance in skeletal muscle?

A

The arrangement of the numerous myofibrils which have a repeating pattern of myosin and actin (myofilaments)

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

What are myofibrils?

A

Tubular structures that make up the majority of muscle fibres. Myofibrils are composed of repeating protein units called myofilaments (actin and myosin)

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

What are the two types of myofilaments?

A

Actin and myosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the cytoskeleton present in all cells formed from?
Actin and myosin (different arrangement in muscle fibres - specialised for contraction)
26
What is actin?
Thin myofilament that forms light bands
27
What is myosin?
Thick myofilament that forms dark bands
28
How are myofibrils divided into sarcomeres?
By Z lines which bisect the light bands (actin anchored to Z lines)
29
What are sarcomeres?
The contractile units of skeletal muscle
30
How does muscle contract?
When the muscle fibre is excited, actin slides over myosin by the sliding filament model causing the shortening of the sarcomeres and therefore the myofibril shortens.
31
What is the I band composed of?
Actin filaments only. Bisected by Z line
32
What is the A band composed of?
Myosin and overlapping actin filaments
33
What is the H band composed of?
Myosin filaments only
34
What is the name of the mechanism that causes sarcomeres to contract?
Sliding filament mechanism
35
What happens to a sarcomere when the muscle fibre contracts?
I bands shorten, H bands shorten, A bands stay constant, more overlapping of myosin and actin, Z lines move closer together.
36
Which neurones innervate skeletal muscle fibres?
Somatic motor neurones
37
What is a motor unit?
A single motor neurone together with all the muscle fibres it innervates.
38
What is a neuromuscular junction?
The synapse which connects a motor neurone and muscle fibre
39
What is excitation-contraction coupling?
the transduction of an action potential to a muscle contraction
40
What are the steps of excitation-contraction coupling?
1. action potential in motor neurone converted to acetylcholine at neuromuscular junction 2. detected by receptors on sarcolemma 3. depolarisation (Na+ influx) spreads down T tubules to SR triggering an action potential in muscle fibres 4. Ca2+ released from SR and binds to troponin 5. contraction
41
What is the sarcolemma?
the plasma membrane of skeletal muscle cells
42
What are T-tubules
Invaginations of the sarcolemma into the sarcoplasm which wrap around myofibrils and are continuous with the extracellular space
43
What is the sarcoplasmic reticulum?
modified smooth endoplasmic reticulum that stores concentrated Ca2+ (when muscle fibre relaxed)
44
What is the function of T-tubules and the sarcoplasmic reticulum?
Support synchronous contraction of sarcomeres
45
What are special adaptation of muscle fibres?
Modified sarcolemma with pores and T tubules. Modified sarcoplasmic reticulum. Arrangement of myofilaments (actin and myosin) in myofibrils.
46
Where is cardiac muscle found?
Only in the heart
47
Which branch of the nervous system controls cardiac muscle?
Autonomic
48
Structure of cardiac muscle cells (cardiomyocytes)
Striated, elongated, branched, cylindrical cells with 1-2 nuclei.
49
Why is cardiac muscle striated?
Similar arrangement of myofibrils as skeletal muscle.
50
What are the 3 layers of the heart wall?
Pericardium, myocardium, endocardium
51
What is the pericardium?
The outer supporting fibrous connective tissue layer of the heart wall
52
What is the myocardium?
The (thick) layer of cardiac muscle tissue
53
What is the endocardium?
Inner, single layer of endothelial cells
54
By what name is the endocardium known as in the rest of the cardiovascular system?
Endothelium
55
What is the name of cardiac muscle cells?
Cardiomyocytes
56
Which type of connective tissue supports the rich capillary network in the cardiac muscle?
Reticular connective tissue
57
What are intercalated disks?
specialised intercellular junctions containing desmosomes and gap junctions that allow depolarisation to spread through cardiomyocytes.
58
What is the function of gap junctions?
Allow ions and signals to pass freely between cells
59
Similarities between cardiac and skeletal muscle
sarcomeres, T-tubules, sarcoplasmic reticulum, numerous mitochondria, glycogen and lipid granules (energy), contraction via sliding-filament mechanism
60
What is the name of the specialised cardiac muscle cells that initiate and distribute contractions to cardiomyocytes?
The conducting system
61
What is meant by cardiac muscle cells acting as a syncytium?
All cells work in a single unit due to connection via intercalated disks
62
Differences between skeletal and cardiac muscle
- cardiac muscle is under autonomic control while skeletal muscle is under somatic control - in cardiac muscle, Ca2+ leaks slowly from SR - skeletal muscle doesn't have conducting system, instead each fibre is innervated by motor neurone - intercalated disks
63
How do the cells in the SAN set the basic heart rhythm?
Pacemaker cells undergo spontaneous depolarisation due to slow leaking of Ca2+ from SR
64
What is the sequence of the conducting system of the heart?
- initiated by pacemaker cells in sinoatrial node - contraction of LA and RA - depolarisation reaches atrioventricular node - travels to atrioventricular Bundle of His - to Purkinje fibres - relayed to cardiac muscle fibres - cardiomyocytes contract
65
How is the rate of the inherent heart rhythm modulated?
Autonomic nervous stimulation and hormonal stimulation
66
Where is smooth muscle located?
Lining hollow, visceral organs
67
Function of smooth muscle
to propel lumen contents e.g. bolus in peristalsis
68
Structure of smooth muscle cell - shape, nuclei, striation
elongated, spindle-shaped cells with tapered ends. Single centrally located nuclei. Non-striated (no sarcomeres)
69
Layers of the oesophagus
epithelium, lamina propria, muscularis mucosae, submucosa, muscularis propria (inner circular layer, outer longitudinal layer), adventitia
70
What is the name of the two layers of smooth muscle surrounding the submucosa in the oesophagus?
Muscularis propria (inner circular, outer longitudinal)
71
Why are the 2 layers of muscularis propria at right angles?
The inner layer constricts the lumen while the outer layer shortens the tract length - specialised for peristalsis
72
Where is the parasympathetic ganglia located in the oesophagus?
Between the 2 layers of smooth muscle making up the muscularis propria
73
Function of the parasympathetic NS on the oesophagus
Regulates intensity of peristalsis
74
How are actin and myosin arranged in smooth muscle cells?
Criss-cross lattice
75
How is actin anchored to the cytoplasm and cell membrane of smooth muscle cells?
Via dense bodies
76
Function of dense bodies
Attach adjacent smooth muscle cells together to transmit the contractile forces through the tissue. Anchor actin to cytoplasm and plasma membrane.
77
Location of myosin in smooth muscle cell
Distributed throughout cytoplasm
78
What is desmin?
An intermediate filament found in smooth muscle cells that help to anchor actin and allow myosin to slide over it which is aided by dense bodies
79
How does a smooth muscle cell change shape when contracted?
Elongated -> shortened and globular
80
How does smooth muscle differ in speed of contraction and energy consumption compared to skeletal and cardiac muscle.
Contract more slowly. Uses less energy

BDS1 (105 decks)

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