Brainscape's Knowledge GenomeTM

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


See full index

Anatomy Exam 1: Lectures 1-7 > Lecture 4: Muscle Tissue and Muscles > Flashcards

Lecture 4: Muscle Tissue and Muscles Flashcards

1
Q

What are the four types of muscle tissues?

A

skeletal, smooth, cardiac, branchiomeric

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

What are the characteristics of skeletal muscles?

A

Also called striated or voluntary
Muscle fibers have striated or banded appearance
Under voluntary control
Typically attached directly or indirectly to skeletal system

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

What are the characteristics of smooth muscle?

A

Not striated
Generally involuntary
Spindle shaped mononucleated cells with centrally located nuclei
commonly associated with viscera

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

What are the characteristics of cardiac muscle?

A

Only found in heart
Striated
Involuntary
Consists of chains of individual cells that are mononuclear and striated
Have specialized intercellular junctions called intercalated discs

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

What are the characteristics of branchiomeric muscle?

A

Associated with pharyngeal arches
Transition between smooth and striated muscle tissue
Innervated by cranial nerves

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

In what ways can muscles be named based on characteristics?

A 
Shape
origin-insertion
function
relative size
fiber arrangement
location
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is an agonist?

A

muscle doing the desired action, is a mover when its contraction contributes to the desired movement of a joint, classified as prime mover or assistant mover

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

What is a prime mover?

A

muscle whose primary function is to cause the particular movement, makes strong contribution

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

What is an assistant mover?

A

ability to assist in the movement but is only of secondary importance to the movement

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

What is an antagonist?

A

Muscle that opposes the agonist

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

What is a synergist?

A

nullify one or more actions of another muscle
Will cause the opposite motion of the prime mover without assisting in the movement
Example: tricep to the biceps elbow flexion, so that biceps can person supination of the forearm

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

What is a fixator?

A

stabilize the segment (bone) on which another segment (bone) moves

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

What is muscle contraction?

A

a response to a stimulus

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

What are the types of muscle contraction?

A

isometric, isotonic, concentric, eccentric

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

Isometric vs isotonic contraction

A

isometric: length of muscle does not change
isotonic: length of muscle does change

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

Concentric vs eccentric contraction

A

concentric: muscle gets shorter
eccentric: muscle gets longer

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

What are flexor muscles?

A

muscles that pass anterior to the axis, can shorter about one half of total length

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

What extensor muscles?

A

muscles that pass posterior to the axis

19
Q

What are abductors?

A

muscles that pass lateral to a joint

20
Q

What is an origin?

A

usually proximal, may be fixed with regard to movement

21
Q

What is an insertion?

A

Usually distal, may be fixed with regard to movement

22
Q

What are the characteristics of tendons?

A 
Attachment between muscle fibers and bone
Dense collagenous connective tissue
Surrounded by peritendineum
Bundles of collagen fibers
Poorly vascularized
23
Q

What is an aponeuroses?

A

flat, fan shaped tendons typically given rise to other tendons

24
Q

What is the hierarchical structure of skeletal muscles (smallest to larger)?

A

myofilament-myofibril-myofiber-fascicle-muscle

25
Q

What are the two types of myofilaments?

A

actin and myosin

26
Q

What are myofilaments organized into?

A

sacromeres

27
Q

What is a myofibril?

A

Chain of sarcomeres

28
Q

What is a myofiber?

A

bundle of myofibril, referred to muscle cell, each fiber formed from many fused myoblasts

29
Q

what is a fascicle?

A

under of myofibers

30
Q

What is a muscle

A

composed of varying numbers of fascicles

31
Q

What is the endomysium?

A

Surrounds each muscle fiber

Lies outside sarcolemma (cell membrane)

32
Q

What is the perimysium?

A

Surrounds each fascicle

33
Q

What is the epimysium?

A

Surrounds each muscle
Becomes continuous with tendons
Attached to periosteum

34
Q

What is actin?

A

Thin filamentous protein polymer
Each filament is made up of two helical wound polymers of g actin
Associated molecules: tropomyosin and troponin

35
Q

What is myosin?

A

Bundles of long molecules: tail + ATPase head, head attached to tail via swivel mechanism
Heads attach to binding sites on actin filaments
Attach-swivel-release cycles allow myosin and actin to slide along one another in opposite directions, products contraction

36
Q

What is the z line?

A

separate adjacent sarcomeres in a fibril, composed of Z- actin

37
Q

What is the I band?

A

located on either side of Z-line, make up ends of each sarcomere, composed entirely of actin

38
Q

What is the A band?

A

located in middle of sarcomere, composed of both actin and myosin

39
Q

What is the H band?

A

in middle of each A band made of myosin, changes width during contraction

40
Q

What is a motor unit?

A

a motor neuron and all the myofibers it innervates

41
Q

What is the mechanism for muscle contraction?

A

Action potential arrives at sarcolemma from a motor neuron
Synaptic plate is the intervention point between the axon and the sarcolemma
Action potential is conducted from sarcolemma into the interior of the myofiber via T- tubules
Action potential carried by t-tubules causes the release of calcium ions from the sarcoplasmic reticulum cisternae
Calcium ions initiate mechanism by which actin and myson filaments slide over one another resulting in a contraction

42
Q

What are the characteristics of fast twitch muscles?

A 
light, white 
Fatigue easily 
Contract rapidly
rely on glycolysis 
Have a small number of mitochondria
Have a low concentration of myoglobin
Have a high concentration of ATPase
43
Q

What are the characteristics of slow twitch fibers?

A 
dark, red
Fatigue resistant 
Contract slowly
Rely on oxidative phosphorylation
Large number of mitochondria
High concentration of myoglobin 
Low concentration of ATPase

Anatomy Exam 1: Lectures 1-7 (9 decks)

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