Exam 3: Ch. 9 Flashcards
1
Q
Functions of Muscular System
A
- Movement of the body
- Maintenance of posture
- Respiration
- Production of body heat
- Communication
- Constriction of organs and vessels
- Contraction of the heart
2
Q
Contractibility
A
ability of a muscle to shorten with force
3
Q
Excitability
A
capacity of muscle to respond to a stimulus (from our nerves)
4
Q
Extensibility
A
muscle can be stretched to its normal resting length and beyond to a limited degree
5
Q
Elasticity
A
ability of muscle to recoil to original resting length after stretched due to sarcomere
6
Q
Location of skeletal muscle
A
- bones
2. skin
7
Q
Location of smooth
A
hollow internal organs
ex. vessels, uterus, arrector pili
8
Q
Location of cardiac muscle
A
only heart
9
Q
Control/nerves of skeletal muscle
A
voluntary
10
Q
Control/nerves of smooth muscle
A
involuntary
11
Q
Control/nerves of cardiac muscle
A
involuntary
12
Q
Function of skeletal muscle
A
- movement
- support
- communication
13
Q
Function of smooth muscle
A
internal organ regulation
14
Q
Function of cardiac muscle
A
cardiac circulation
15
Q
Multi or unicellular: skeletal muscle
A
multicellular
16
Q
Multi or unicellular: smooth
A
unicellular
17
Q
Multi or unicellular: cardiac
A
unicellular
18
Q
Structure of skeletal muscle
A
myofibril filaments
19
Q
Structure of cardiac muscle
A
- gap junctions
2. allow ions to move through Ca, Na, K
20
Q
How to identify skeletal muscle
A
- nuclei on same line
2. small vertical lines (sarcomeres/striations)
21
Q
how to identify smooth muscle
A
does not have striations
22
Q
how to identify cardiac muscle
A
- striations
2. intercalated disks btw cells
23
Q
epimysium
A
CT surrounding whole muscle
24
Q
perimysium
A
CT surrounding fascicle
25
endomysium
CT surrounding individual muscle fiber
26
muscular fascia
CT sheet
1. external to epimysium
2. holds muscles together and separates them into functional groups
27
Thin filament is called
actin
28
thick filament is called
myosin
29
myofilament is composed of
protein threads
30
sarcomeres
1. repeating units of myofilaments
2. smalled structural and functional unit
3. allows elasticity
31
parts of a muscle: smallest to largest
1. myofibril
2. myofiber
3. fasciculum/fascicle
4. muscle
32
myofibril part: transverse tubule is: the extension of... and surrounds the...
1. extension of membrane
| 2. surrounds myofibril for depolarization for muscle contraction and release Ca++
33
sarcoplasmic reticulum: stores... for contraction
calcium
34
mitochondria produces...for muscle relaxation
ATP
35
cramps happen when ATP... and Ca++ is not...
ATP relaxes and Ca++ is NOT released
36
3 units of actin
1. F actin molecules
2. tropomyosin
3. troponin
37
2 units of myosin molecule
head and tail
38
ATP's role in cross-bridge movement
separates myosin head from actin
39
Sarcomere: 2 structures that get smaller
I band and H zone
40
Sarcomere: Z disk
point of attachment for actin myofilaments
41
Sarcomere: I band contains ONLY...
thin filaments
42
Sarcomere: how to identify I band
lightest colored band with dark stripe
43
Sarcomere: how to identify A band
dark colored band with thick filaments
44
Sarcomere: length does not change when sarcomere shorten
A band
45
Sarcomere: this area is the length of thick filaments
A band
46
Sarcomere: This area contains overlapping thin and thick filaments
A band
47
Sarcomere: how to identify H zone
lighter colored band in btw two I bands
48
Sarcomere: this area contains ONLY thick filaments
H zone
49
Sarcomere: these two's lengths decreases when sarcomere shortens
H zone and I band
50
Sarcomere: how to identify M line
center of H zone
51
Sarcomere: M line is point of attachment for...
the thick filaments
52
Plasma membrane of skeletal muscle fiber
Sarcolemma
53
Neuromuscular junction: Found in synaptic end bulbs of axon terminal; contains neurotransmitter molecules
synaptic vesicles
54
Neuromuscular junction: Area of sarcolemma across from synaptic end bulbs of axon terminal; contains neurotransmitter receptors
motor end plate
55
Neuromuscular junction: Space between synaptic end bulbs of axon terminal and sarcolemma
synaptic cleft
56
Neuromuscular junction: Divides into synaptic end bulbs at neurotransmitter junction
axon terminal
57
Neuromuscular junction: Parts of axon terminal that form neuromuscular junction
synaptic end bulb
58
Sarcomere: region in A band where actin and myosin do not overlap
H zone
59
Skeletal muscle fibers: what pump is needed for muscle contractions?
Na+/K+ pump
60
Skeletal muscle fibers: + or - at rest?
- at rest b/c more - charge inside of cell
61
Na+/K+ pump: Channels use diffusion or ATP?
diffusion
62
Na+/K+ pump: depolarization
becomes more positive
63
Na+/K+ pump: repolarization
return to negative at rest
64
Skeletal muscle: all or none principle
need several stimuli to get response
65
Action potential: how directions does action potential go in?
only one b/c it's hyper polarized
66
3 phases of muscle twitch
1. lag phase
2. contraction phase
3. relaxation phase
67
motor unit
a single motor neuron and all muscle fibers innervated by it
68
How many motor units needed? Eye movement, playing violin
many
69
How many motor units needed? Quads
1 b/c one movement
70
Muscle contraction: complete tetanus
no relaxation btw contractions
71
Active tension
force applied to an object to be lifted when a muscle contracts
72
Passive tension
tension applied to load when a muscle is stretched but not stimulated
73
Muscle contractions: isometric and EX
no change in length but tension increases
| ex. postural muscles
74
Muscle contractions: isotonic
change in length but tension is constant
75
Muscle contractions: concentric
overcomes opposing resistance and muscle shorten
76
Muscle contractions: eccentric and EX
tension maintained but muscle lengthens
| ex. holding grocery bags
77
Muscle contractions: muscle tone
constant tension by muscles for long periods of time
78
3 types of muscle fatigue
1. psychological/mind
2. muscular/lack of ATP
3. synaptic/lack of acetylcholine
79
when does physiological contracture and rigor mortis happen?
after dying
80
How much ATP does aerobic exercise use?
a lot
81
How much ATP does anaerobic exercise use?
limited
82
Slow twitch muscles in chicken (dark meat)
legs
83
Fast twitch muscles in chicken (white meat)
breasts
84
F: slow twitch
endurance/fatigue-resistance
85
F: fast twitch
responds rapidly
86
Skeletal or smooth: Shape of tissue, location: multinucleated, many fibers are fused together, near bones and skin
skeletal
87
Skeletal or smooth: Shape of tissue, location: single cells, no fusion, around hollow organs, for peristalsis
smooth
88
Skeletal or smooth: sarcolemma: has T tubules
skeletal
89
Skeletal or smooth: sarcolemma: has Caveolae
smooth
90
Skeletal or smooth: Boundaries of the contractile unit: Z disks
skeletal
91
Skeletal or smooth: Boundaries of the contractile unit: dense bodies
smooth
92
Skeletal or smooth: Storage of Calcium: sarcoplasmic reticulum
skeletal
93
Skeletal or smooth: Storage of Calcium: extracellular calcium is used for contraction
smooth
94
Skeletal or smooth: role of calcium: Contraction by in changes in conformation
skeletal
95
Skeletal or smooth: role of calcium: contraction by activating enzymes
smooth
96
Skeletal or smooth: contraction: ATP binds to the head of the myosin and Ca is pumped into the SER
skeletal
97
Skeletal or smooth: contraction: An enzyme removes the phosphate group
smooth
98
Smooth muscle is under the control of...
hormones
99
Does smooth muscle need ATP for relaxation?
NO
100
Does smooth muscle need Ca++ for contraction?
YES
101
Effects of aging on skeletal muscle
Reduced muscle mass
Increased time for muscle to contract in response to nervous stimuli
Reduced stamina
Increased recovery time
Loss of muscle fibers
Decreased density of capillaries in muscle
102
Skeletal or smooth: which uses Ca++ to contract?
both
103
Skeletal or smooth: which uses ATP for relaxation?
skeletal
