Chapter 6- Muscular System Flashcards
1
Q
What are muscles responsible for
A
All types of body movement
2
Q
What are the 3 basic types of muscle in the body
A
. Skeletal
. Cardiac
. Smooth
3
Q
What is the only muscle involved in the muscular system
A
Skeletal
4
Q
Skeletal muscle is attached by what to bones
A
Tendons
5
Q
Skeletal muscle fibers are what
A
Elongated and multinucleated
6
Q
What are skeletal muscle fibers also known as
A
Striated muscle
7
Q
What kind of muscle is skeletal muscle since it’s subject to conscious control
A
Voluntary muscle
8
Q
Skeletal muscle cells are surrounded and bundled by what
A
Connective tissue
9
Q
What are the 4 types of connective tissue in skeletal muscle
A
. Endomysium
. Perimysium
. Epimysium
. Fascia
10
Q
What encloses a single muscle fiber
A
Endomysium
11
Q
What wraps around a fascicle of muscle fibers
A
Perimysium
12
Q
What covers the entire skeletal muscle
A
Epimysium
13
Q
What is on the outside of the Epimysium
A
Fascia
14
Q
The Epimysium of skeletal muscle blends into what
A
A connective tissue attachment
15
Q
What are the 2 connective tissue attachments
A
. Tendons
. Aponeuroses
16
Q
What are mostly made of collagen fibers and often cross a joint because of their toughness and small size
A
Tendons
17
Q
What attach muscles indirectly to bones, cartilages or connective tissue coverings
A
Aponeuroses
18
Q
What are the 4 functions of skeletal muscle functions
A
. Produce movement
. Maintain posture and body position
. Stabilize joints
. Generate heat
19
Q
What are specialized plasma membrane
A
Sarcolemma
20
Q
What are myofibrils
A
Long organelles inside muscle cells
21
Q
What are the 2 types of myofibrils
A
. Light I bands
. Dark A bands
22
Q
What do light I bands and dark A bands do
A
Give muscle it’s striated appearance
23
Q
Which band contains only thin filaments
A
I band
24
Q
What is the Z disc in I bands
A
A midline interruption and marks the end of the contractile unit
25
Which band contains the entire length of the thick filaments
A band
26
Which band has a H zone that is a lighter central area and a M line is in the center of H zone
A Band
27
What is a contractile unit of a muscle fiber and also the structural and functional unit of skeletal muscle
Sarcomere
28
What are the 2 myofilaments for the organization of the sarcomere
. Thick filaments
| . Thin filaments
29
What are myosin filaments
Thick filaments
30
What are actin filaments
Thin filaments
31
What are thick filaments composed of
Protein myosin
32
What do thick filaments contain
ATPase enzymes to split ATP to release energy for muscle contractions
33
What type of projections do thick filaments posses
Myosin heads
34
What do myosin heads do in thick filaments
Form cross bridges for thick and thin filaments to contract
35
What are thin filaments composed of
The contractile protein
36
Where is actin anchored
To the Z disc
37
When the a band is at rest there is a zone that lacks actin filaments called what
The H zone
38
What happens during contraction
H zones disappear as actin and myosin filaments overlap
39
What surrounds the myofibril
Sarcoplasmic reticulum
40
What does the sarcoplasmic reticulum store and release
Calcium
41
What are the 4 special functional properties of skeletal muscles
. Irritability
. Contractility
. Extensibility
. Elasticity
42
What’s the ability to receive and respond to a stimulus
Irritability
43
What’s the ability to forcibly shorten when an adequate stimulus is received
Contractility
44
What’s the ability of muscle cells to be stretched
Extensibility
45
What’s the ability to recoil and resume resting length after stretching
Elasticity
46
Skeletal muscles must be stimulated by what to contract
Neuron
47
What is a one motor neuron and all the skeletal muscle cells stimulated by that neuron
Motor unit
48
What is an association site of axon terminal of the motor neuron and sarcolemma of a muscle cell
Neuromuscular junction
49
What a gap between a nerve and muscle filled with interstitial fluid
Synaptic cleft
50
What is a chemical released by nerve upon arrival of nerve impulse in the axon terminal
Neurotransmitter
51
What is the neurotransmitter that stimulates skeletal muscle
Acetylcholine
52
What is step 1 at the neuromuscular junction
Nerve impulse reaches the axon terminal of the motor neuron
53
What is step 2 at the neuromuscular junction
Calcium channels open and calcium ions enter the axon terminal
54
What’s step 3 at the neuromuscular junction
Calcium ion entry causes some synaptic vesicles to release acetylcholine
55
What is step 4 at the neuromuscular junction
ACh diffuses across the synaptic cleft and attaches to receptors on the sarcolemma of the muscle cell
56
What is step 5 of the neuromuscular junction
If enough ACh is released, the sarcolemma becomes temporarily more permeable to sodium ions
57
What is step 6 of the neuromuscular junction
Depolarization opens more sodium channels that allow sodium ions to enter the cell
58
What is step 7 of the neuromuscular junction
Acetylcholinesterase breaks down acetylcholine into acetic acid and choline
59
What happens potassium ions diffuse out of the cell
Cells return to its resting state
60
What happens when the sodium potassium pump moves sodium and potassium ions back to their original positions
Cells return to its resting state
61
What are the 4 steps for sliding filaments
. Cross bridge formation
. Power stroke
. Cross bridge detachment
. Cocking of myosin head
62
What is it called when a myosin head attaches to actin binding sites to form a cross bridge
Cross bridge formation
63
What is it called when a myosin head pulls actin toward the m line
Power stroke
64
What is it called when a myosin head detaches from actin
Cross bridge detachment
65
What is it called myosin prepares for another cycle
Cocking of myosin head
66
What are the 2 ways graded responses can be produced
. By changing the frequency of muscle stimulation
| . By changing the number of muscle cells being stimulated at one time
67
What is a single, briefcase jerky contraction
Muscle twitch
68
In most types of muscle activity, nerve impulses are delivered at a what rate
Rapid rate
69
Contractions are followed by what
Another contraction
70
What occurs when stimulations become more frequent
Infused (incomplete tetanus)
71
What is achieved when the muscle is stimulated so rapidly that no relaxation occurs
Fused tetanus
72
What does muscle respond too
Stronger stimuli
73
What depends upon the number of fibers stimulated
Muscle force
74
Contraction of more fibers results in greater what
Muscle tension
75
When all motor units are active and stimulated, the muscle contraction is what
As strong as it can get
76
What is the only energy source that can be used to directly power muscle contraction
ATP
77
Where is ATP stored in small amounts
Muscle fibers
78
What are the 3 pathways to regenerate ATP
. Direct phosphorylation
. Aerobic pathway
. Anaerobic glycolysis and lactic formation
79
If muscle activity is strenuous and prolonged what happens
Muscle fatigue occurs
80
What are the 3 factors that contribute to muscle fatigue
. Ion balances
. Oxygen deficit
. Decrease in energy supply
81
How is the oxygen deficit repaid
Rapid, deep breathing
82
What is the state of continuous partial contractions
Muscle tone
83
What increases muscle size, strength, and endurance
Exercise
84
What results in stronger, more flexible muscles with greater resistance to fatigue
Aerobic exercise
85
What increases muscle size and strength
Resistance exercise
86
What decreases angle of joint and brings two bones closer together
Flexion
87
What increases angle or distance between two bones or body parts
Extension
88
What are extensions greater than 180 degrees
Hyperextension
89
What is a movement of bone around its longitudinal axis
Rotation
90
What is moving a limb away from the midline
Abduction
91
What’s moving a limb towards the midline
Adduction
92
What’s it called when proximal end is stationary, distal end moves in circle
Circumduction
93
What’s it called when you point toes toward your head
Dorsiflexion
94
What it called when you point your toes away from your head
Plantar flexion
95
What’s it called when you turn sole of foot medially
Inversion
96
What’s it called when you turn sole of foot laterally
Eversion
97
What’s it called palm facing up
Supination
98
What’s it called when palms are facing down
Pronation
99
What’s it called when thumb touches tips of fingers on same hand
Opposition
100
What raises the eyebrows
Frontalis
101
What pulls scalp posteriorly
Occipitalis
102
Closes eyes, squint, blink, and wink
Orbicularis oculi
103
What protrudes lips
Orbicularis Oris
104
What’s flattens and compresses the cheek
Buccinator
105
What raises corners of mouth upward
Zygomaticus
106
What closes the jaw
Masseter and temporalis
107
What pulls corners of mouth inferiority
Platysma
108
What rotates the head toward opposite shoulder
Sternocleidomastoid
109
What adducts and flexes the arms
Pectoralis major
110
What abducts the arm
Deltoid
111
What are the breathing muscles
Intercostal muscles
112
What flexes the vertebral column
Rectus abdominis
113
What flexes vertebral column, rotates trunk, and bends laterally
External and internal oblique
114
What compresses the abdomen
Transversus abdominis
115
What extends the head, elevates, depresses, adducts, and stabilizes the scapula
Trapezius
116
What extends and adducts the humerus
Latissimus Dorsi
117
What are back extensors
Erector spinae
118
What flexes the spine laterally, together- extends lumbar spine
Quadratus lumborum
119
What are the 2 things that flex the elbow
. Biceps brachii
| . Brachialis
120
What extends the elbow
Triceps brachii
121
What flexes the wrist and fingers
Forearm flexor group
122
What flexes the forearm
Brachioradialis
123
What extends the wrist and fingers
Forearm extensor group
124
What extends the hip
Gluteus Maximus
125
What abducts the hip
Gluteus medius
126
What flexes the knee and extends the hip
Hamstring muscles
127
What flexes the hip
Iliopsoas
128
What adducts the thigh
Adductor muscles
129
What flexes the thigh
Sartorius
130
What extends the knee
Quadriceps
131
What dorsiflex and invert the foot
Tibialis anterior
132
What is the toe extension
Extensor digitorum longus
133
What is the plantar flex and evert foot
Fibularis muscles
134
What are the 2 plantar flex foot
. Gastrocnemius
| . Soleus
