Chapter 10: Muscular system Flashcards
1
Q
muscles account for roughly __ % of body weight
A
50
2
Q
performance of muscles varies based on __ and __
A
fiber organization, skeletal attachments
3
Q
what are the two divisions of the skeletal muscle system?
A
axial and appendicular
4
Q
what is the function of axial muscles?
A
support and position axial skeleton
5
Q
what is the function of appendicular muscles?
A
support, move, and brace limbs
6
Q
what is a fascicle?
A
a bundle of muscle fibers
7
Q
the fascicles in a parallel muscle are__
A
parallel to long axis
8
Q
give an example of a parallel muscle
A
biceps brachii
9
Q
how much do parallel muscles shorten?
A
~30%
10
Q
describe structure of convergent muscle
A
fascicles extending over broad area, converging at common attachement point
11
Q
which pulls harder? Convergent or parallel muscles?
A
parallel
12
Q
give an expample of a convergent muscle
A
pectoralis major
13
Q
structure of pennate muscle
A
fascicles form angle with tendon
14
Q
do tendons move more in parallel or pennate muscles?
A
parallel muscles
15
Q
pennate muscles have more ___ than same-sized parallel muscle
A
myofibrils/fibers
16
Q
which produces more tension, parallel or pennate?
A
pennate
17
Q
what are the 3 types of pennate muscles?
A
- unipennate
- bipennate
- multipennate
18
Q
structure of unipennate muscles?
A
all fibers on one side of tendon
19
Q
give an example of unipennate muscle
A
extensor digitorum
20
Q
structure of bipennate muscle
A
fibers insert on both sides of tendon
21
Q
give example of bipennate muscle
A
rectus femoris
22
Q
structure of multipennate muscle
A
tendon branches within pennate muscle
23
Q
give an example of multipennate muscle
A
deltoid
24
Q
structure of circular/ spinchter muscles
A
concentric rings of fascicles
25
give an example of circular muscle
orbicularis oris
26
what is a lever?
rigid structure that moves when force applied overcomes the load
27
what is a fulcrum?
a fixed point on which a lever pivots
28
what is a first class lever?
fulcrum between AF and L
29
example of 1st class lever in body
splenius capitis and semispinalis capitis muscles
30
what is a 2nd class
load between AF and f
31
what is a 3rd class lever?
fulcrum, af, load
32
example of 1st class lever in body
neck extension at atlanto-occipital joint
33
example of second class lever in body
plantar flexion at ankle joint
34
example of third class lever in body
flexion at elbow
35
thrid class levers have increased __ and ___, but decreased ___
speed and distance, force
36
second class levers have increased __, but decreased ___ and __
force; speed and distance
37
origin
where muscle attaches
38
most origins are __, but can be __-
bones, but can be connective tissue
39
where is the origin in relation to the insertion?
proximal
40
insertion
where movable end of muscle attaches
41
agonist
prime mover
42
what is the agonist in elbow flexion?
biceps brachii
43
synergist
muscle that helps prime mover
44
synergist in elbow flexion
bracioradialis
45
antagonist
muscle whose action opposes that of the prime mover
46
antagonist in elbow flexion
triceps brachii
47
deltoid
triangle
48
orbicularis
circle
49
brevis
short
50
longissimus
longest
51
longus
long
52
major
larger
53
maximus
largest
54
vastus
great
55
levator
raising
56
what is the originof muscles in facial expression?
skull
57
what are the insertions for muscles in facial expression?
superficial fascia and dermis of skin
58
what are the origins of the extrinsic eye muscles?
sphenoid and maxillary bone around optic canal
59
what are the 6 extrinsic eye muscles?
1. superior oblique
2. inferior oblique
3. superior rectus
4. lateral rectus
5. medial rectus
6. inferior rectus
60
action of inferior rectus
eye looks down
61
action of medial rectus
eye looks medially
62
action of superior rectus
eye looks up
63
action of lateral rectus
eye looks laterally
64
action of superior oblique
eye rolls: looking down and lateral
65
action of inferior oblique
eye rolls: looking up and laterally
66
which 2 muscles are involved in chewing?
masseter and temporalis
67
action of masseter in chewing
raises mandible and closes jaw
68
action of temporalis in chewing
raises mandible
69
which 3 muscles are closely associated with chewing?
1. tongue
2. of pharnyx (swallowing)
3. of neck
70
muscles of the vertebral column originate and insert where?
vertebral processes
71
there are few __ in vertebral muscle
flexors
72
what are the 3 main muscles of the abdomen?
1. external oblique
2. internal oblique
3. rectus abdominis
73
muscles of the appendicular skeleton are grouped by ___ and ___
actions and origins
74
muscles of the pectoral girdles originate __ and insert __
on axial skeleton; on clavicle/scapula
75
muscles that ove the arm originate __ and insert __
on pectoral girdle and rib cage; on humerus
76
muscles that move the forearm and hand originate __ and insert __
on pectoral girdle and arm; on radius, ulna, and/or carpels
77
extrinsic muscles to the hand originate __ and insert __
on humerus, radius, ulna; on metacarpals and phalanges
78
intrinsic muscles of the hand originate __ and insert __
on carpals and metacarpals; on phalanges
79
muscles that move the thigh originate __ and insert __
in pelvic region; on femur
80
muscles that move the leg originate __ and insert __
on pelvis and femur; on tibia/fibula
81
extrinsic muscles that move the foot/toes originate __ and insert __
on tibia/fibula; on tarsals, metatarsals, plalanges
82
intrinsic muscles that move the foor/toes originate __ and insert ___
on tarsals, metatarsals; phalanges
83
the largest appendicular muscles originate __
on the trunck
84
trunck muscles control ___ scale movement
large
85
structure of muscles of the trunk
large and powerful
86
what are the 2 largest superficial muscles involved in arm movement?
latissimus dorsi and deltoid
87
what are the four rotator cuff muscles?
1. supraspinatus
2. infraspinatus
3. teres minor
4. subscapularis
88
wrist extensors can be seen on what surface?
posterior surface
89
wrist flexors can be seen on what surface?
anterior surface
90
what are the extensor and flexor retinaculum?
wide band of connective tissue holding tendons of muscles in place
91
the biceps brachii origin is __ and inserts on __
scapula; radius
92
action of biceps bracii
flexion of elbow
93
the brachioradiallis origin is __ and inserts on__
humerus; radius
94
action of brachioradiallis
elbow flexion
95
brachiallis origin is __ and inserts on __
humerus; ulna
96
the triceps bracii origin is __ and inserts on __
scapula/humerus; ulna
97
action of triceps brachii
extension of elbow
98
flexors are mostly __ and __
anterior and medial
99
extensors are mostly __ and __-
posterior and lateral
100
what are synovial tendon sheaths?
tubular bursae surrounding tendons where theu cross bony surface
101
carpal tunnel syndrome is caused by inflammation of __
flexor retinacculum and synovial sheaths
102
flexors of the knee originate __ and extend along __ and __ surfaces of the thigh
on pelvic girdle; posterior and medial
103
extensors of the knee originate ___ and extend along __ and __ surfaces of the thigh
femoral surface; anterior and lateral
104
what is the quadriceps femoris?
collective name for the 4 knee extensors that all insert on quad
105
how many vastus muscles surrounf the rectus femoris?
3
106
all 4 quad muscles insert on the __
patella
107
what are the 3 flexors of the knee?
1. biceps femoris
2. semimembranosus
3. semitendinosus
108
the biceps femoris inserts
tibia
109
the semimembranosus inserts on
tibia
110
the semitendinosus inserts on
tibia
111
what are the 4 extensors of the knee?
1. rectus femoris
2. vastus intermedius
3. vastus lateralis
4. vastus medialis
112
where do the 4 knee extensors insert?
patellar ligamnet
113
what are the 2 largest muscles involved in ankle movement?
gastrocnemius and soleus
114
what are intermuscular septa?
fibrous parttions that separate limb muscles into differnet compartments
115
each compartment has:
1. muscles sharing common functions
| 2. its own blood and nerve supply
116
what is compartment syndrome?
trauma to limb can cause bleeding, which compresses bv and a lack of blood causes starvation and death
