Brainscape's Knowledge GenomeTM

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


See full index

HCS102 Human Physiology > Muscle physiology > Flashcards

Muscle physiology Flashcards

1
Q

What are the types of muscles?

A

Skeletal muscle
Cardiac muscle
Smooth muscle

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

Explain each one

A

Skeletal: attached to bone, facilitate movement around joints
Cardiac: only in hear, moves blood through circulatory system
Smooth muscle: muscle for internal organs and tubes, influences movement of material into, out of and within body

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

What is the characteristic skeletal and cardiac muscle share?

A

Both are striated muscle that can be seen thanks to light and dark bands under microscope

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

How is skeletal muscle attached to bones?

A

Attached via tendons

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

What are the types of muscle twitches?

A

Type I (slow twitch)
Type II (fast twitch oxidative)
Type IIb (fast twitch glycolytic)

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

Explain each type

A

Type I: subset of skeletal muscle associated with endurance type performance
Type II: associated with performance where power needs to be generated (100m sprint) - uses oxidative pathway
Type IIb: associated with power generation but its explosive generation of power (jump, punching, power lifting) - uses glycolytic pathways

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

What is an extensor muscle?

A

Bones moves away from each other when muscle contracts

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

What are muscle fibers?

A

Long, cylindrical cells with up to several hundred nuclei

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

True or false: Are skeletal muscles sheathed in connective tissue?

A

True. Sheathed in connective tissue with groups of adjacent muscle fibers bundled together

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

How do cell organelles names change when they are muscle cells?

A

Sarcoplasm - cytoplasm
Sarcolemma - cell membrane
Sarcoplasmic reticulum - endoplasmic reticulum

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

Explain smooth muscle

A

Found in walls of “tube” such as blood vessels, gi tract in sphincters
Associated with autonomic functions
Hass less myosin than skeletal

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

What influences smooth muscle?

A

Sympathetic and parasympathetic neurons and hormones and paracrine signals

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

Explain contraction in smooth muscle

A

Alternates between contraction and relaxation

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

What is phasic smooth muscle?

A

Muscles that undergo periodic contraction and relaxation cycles

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

What is tonic smooth muscle?

A

Muscle that is continuously contracted

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

How do cells communicate with neighboring cells?

A

Cells that are electrically connected by gap junctions are single unit smooth muscle.
Cells that aren’t link electrically are multiunit smooth muscle

17
Q

How is muscle contraction defined?

A

By how shape of muscle which is contracting changes or by extension or motion

18
Q

What governs muscle contracion?

A

Sliding filament theory

19
Q

What is sliding filament theory?

A

overlapping thick and thin filaments slide past each other in an energy dependent manner as a result of actin-myosin crossbridge movement

20
Q

What are the two important types of contraction?

A

Isometric
Isotonic

21
Q

Explain the effect on muscle these contractions have (Isometric)

A

Isometric: occurs when two ends of a muscle are held at a fixed distance, causes the development of tension with the muscle -> series elastic elements allow the fibers to maintain constant length -> muscle remains static

22
Q

Explain the effect on muscle these contractions have (Isotonic)

A

Isotonic: occurs when on end of muscle is free to move and the muscle shortens -> creates force as the muscle shortens and moves a lot -> constant tension

23
Q

What do the T-tubules of the skeletal muscle fiber do?

A

Allow action potentials to move rapidly into the interior fiber and release calcium from sacroplasmic reticulum

24
Q

What is myofibril of the skeletal muscle fiber?

A

Intracellular bundles of contractile and elastic proteins

25
Q

Explain thick filaments and thin filaments

A

Thick filament: made of myosin
Thin filament: made of actin
Myosin binds to actin -> creates crossbridge between thick and thin filament

26
Q

What is the contractile unit of myofibril?

A

Sacromere

27
Q

What is the myofibril composed of?

A

Of two Z disks and filaments between them

28
Q

What bands are found in the myofibirl?

A

I band: thin filaments
A band: runs in length of thick filaments
Central H band: occupied by tick filament

29
Q

Which disks represent attachment site for myosin and actin?

A

M line and Z disks

30
Q

Explain neuro-muscular junction

A

Synaptic connection between the terminal end of a motor nerve and a muscle
Skeletal muscle concentration require neuronal activation of muscle fibers by either reflex or voluntary neuronal pathways

31
Q

What is the neurotransmitter responsible for signal transduction at neuromuscular junction?

A

Acetylcholine which binds to nicotinic receptors on the post synaptic membrane which possess an integral ion channel protein

32
Q

What impulses are transmitted by neuromuscular junction?

A

Transmits excitatory impulses from motor neurons to muscle fibers

33
Q

What does the process of excitatory impulse involve?

A

Involves the release of acetylcholine from vesicles in the motor neuron axon terminal into the synaptic cleft

34
Q

What happens when the action point reaches the motor neuron?

A

A large volume of ACh is released which leads to sufficient EPP that trigger self-propagating muscle action potential

35
Q

What are motor units?

A

Comprised of one motor neuron and all of the muscle fibers which are innervated by various branches of its axon

36
Q

Explain how large motor units affect axon and cell body

A

Large motor units = larger the axon = larger cell body

37
Q

What is recruitment and summation?

A

Grading the amount of force used in any given action
- recruiting more motor units for given contraction
- increasing the frequency of rate of firing of motor units

38
Q

True or false: all motor units stimulated in muscle contraction

A

False: NOT all motor units stimulated in muscle contraction
-> positive force of contraction increase rate of firing of motor units

39
Q

How many bands of muscle are there?

A

4

HCS102 Human Physiology (8 decks)

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