Chapter 11: The Muscular System Flashcards
1
Q
origin of a muscle
A
- One bone remains stationary or near its original position
- the attachment of a tendon to the stationary bone
2
Q
insertion of a muscle
A
- on the bone that moves
- The attachment of the muscle’s other tendon to the movable bone
3
Q
RMA
A
reverse muscle action
=relatively stationary bone (origin) and movable bone (insertion) switch roles
4
Q
a bone often functions as a ___ and its joint with another bone acts like a ____
A
- lever
- fulcrum
5
Q
when will the load be moves
A
when effort (E) is greater than load (L)
6
Q
what is it based on for lever systems to show mechanical advantage or disadvantage?
A
It is based on the relative distances of the load and effort from the fulcrum
7
Q
mechanical advantage
A
occurs when load is close to fulcrum and effort if farther away from fulcrum (first class lever) = allows large load to be moved a short distance with LITTLE effort
8
Q
mechanical disadvantage
A
effort applied close to fulcrum and load located farther away from fulcrum (third class lever) = expend more effort to move small load but will be faster
9
Q
what are the 5 possible fascicle arrangement?
A
1) parallel muscles
2) fusiform muscles
3) circular muscles
4) triangular muscles
5) pennate muscles
10
Q
fascicles parallel to long axis of muscle; both ends terminate in flat tendons
A
parallel muscles
11
Q
fascicles roughly parallel to long axis of muscle; muscle belly tapers at both ends, terminating in flat tendons
A
fusiform muscles
12
Q
fascicles show a concentric circular pattern; seen in muscular sphincters
A
circular muscles
13
Q
from thick central tendon, fascicles fan-out
A
triangular muscles
14
Q
long tendons run most of muscle length; short fascicles emanate from tendon (feather-shaped)
A
pennate muscles
15
Q
muscle power
A
the more muscle fiber per cm squared, the more forceful its contraction
16
Q
muscle’s range of motion
A
the longer the fiber length, the greater the range of motion
17
Q
how are pennate muscles compared to parallel muscles?
A
pennate muscles are more powerful than parallel muscles but pennate muscle has a smaller range of motion
18
Q
“prime mover” = agonist
A
when the body part is moved by a group of muscles, usually one is the agonist (does most of the work)
19
Q
other muscles of working group
A
synergists
20
Q
when prime mover crosses intermediate joints before reaching joint of its primary action, what do the synergists do?
A
contraction of synergists stabilize intermediate joints
21
Q
what is the prime mover/agonist often opposed by?
A
opposed by an antagonist located in the opposite compartment
22
Q
what happens to antagonist, when agonist shortens?
A
Antagonist lengthens
23
Q
biceps branchii contracts and triceps branchii lengthens
A
- flexion of forearm
- vice versa for extension of forearm
24
Q
biceps branchii and triceps branchii
A
antagonist pair which has equal force resulting isometric contraction
25
muscles that stabilize the prime mover's origin
fixators
26
when deltoid muscle abducts the arm
the scapula must be immobilized by fixators
27
naming based on characteristics of the muscle
1) size
2) shape
3) direction of fibers
4) number of attachments
5) action
28
size
gluteus maximus which is the largest muscle of the buttocks
29
shape
deltoid which is shaped like an inverted triangle
30
direction of fibers
rectus abdominis which is the longitudinal muscle of the abdomen
31
location
occipitofrontalis muscle which covers the frontal bone of skull
32
number of attachments
biceps branchii = 2 origins/heads
| triceos branchii = 3 origins/ heads
33
action
extensor ligament= extends fingers
flexor digitorun= flex fingers
flexor carpi= flex wrist
34
Muscles of facial expression
- Frontal belly of occipitofrontal
- Orbicularis oculi
- Orbicularis oris
- Buccinator
- Zygomaticus major
35
Frontal belly of occipitofrontals
| facial expression
- location: frontal bone of the skull
- function: raises eyebrow, wrinkles brow and can draw scalp interiorly
- origin: epicranial aponeurosis
- insertion: skin overlying supraorbital margin
36
Orbicularis oculi
| facial expression
- location: ring-like muscle encircles eye
- function: causes eyelid to close and responsible for crow's feet at the corners of the eye
- origin: frontal bone of medial orbit, medial palpebral ligament and lacrimal bone
- insertion: lateral palpebral raphe
37
Orbicularis oris
| facial expression
- location: encircles the mouth
- function: used to close and to pucker lips; shapes lips for speaking
- origin: muscles around mouth opening
- insertion: skin at labial commissure
38
Buccinator
| facial expression
- location: in cheek area
- function: compresses cheeks inwards; helps hold food in contact with teeth during chewing
- origin: lateral alveolar processes of the maxilla and mandible
- insertion: orbicularis oris muscle
39
Zygomaticus major
| facial expression
- location: extends from zygomatic arch to corners of the mouth
- function: raises the corners of the mouth (smiling)
- origin: zygomatic bone
- insertion: skin at labial commissure and orbicularis oris
40
Muscles of Mastication (muscles for chewing food and speaking)
- Masseter
- Temporalis
- Platysma
41
Masseter
| mastication
- location: extends from zygomatic arch to mandible
- function: raises mandible, closing jaw for chewing food and speaking
- origin: zygomatic arch and maxilla
- insertion: ramus of mandible
42
Temporalis
| mastication
- location: overlies temporal bone
- function: raises mandible, closing jaw
- origin: temporal bone
- insertion: coronoid process and ramus of mandible
43
Platysma
| mastication
- location: chin, neck and upper chest
- function: depress mandible (opens lower jaw)
- origin: fascia overlying upper portions of pectoralis major and deltoid muscles
- insertion: mandible and skin of lower face
44
Muscles that move the Head
- Sternocleidomastoid
45
Sternocleidomastoid
| move the head
- location: lateral neck (both sides of the body), extends from the clavicle and sternal up to a mastoid process of temporal bone
- function: when both contracts = neck is flexed
when one contracts = head rotates to
opposite side or neck flexes laterally
- origin: manubrium of sternum and clavicle
- insertion: mastoid process of the temporal bone and some fibers
46
Muscles of the trunk
- External and internal obliques, and the transversus abdominis
- Rectus abdominis
- Trapezius
- Other muscles ( External and Internal Intercostal)
47
External and Internal obliques and the transversus abdominis LOCATION
- lateral abdominal wall on each side (run in different direction)
- external and internal obliques between lower ribs and pelvic girdle
- transversus abdominis runs horizontally
48
External and Internal oblique and the transversus abdominis FUNCTION
- 3 sets of muscles tense and support the lateral abdominal wall
external and internal obliques:
- acting unilaterally, produce lateral rotation and lateral flexion of vertebral column
- acting bilaterally, produce flexion of vertebral column
49
External oblique
- origin: ribs #5-12
| - insertion: iliac crest and linea alba
50
Transversus oblique
- origin: costal cartilage #5-10, lumbar fascia, inguinal ligament and iliac crest
- insertion: xiphoid, linea alba, and pubic crest
51
fibrous band that extends from xyphoid process all the way down to the pubic symphysis
linea alba
52
Internal oblique
- origin: iliac crest, inguinal ligament and thoracolumbar, fascia
- insertion: costal cartilages #7-10
53
```
Rectus abdominis
(trunk)
```
- location: runs from pubic bones to ribs and sternum
- function: compresses abdominal cavity and helps flex vertebral column forward
- origin: pubic crest and pubic symphysis
- insertion: xiphoid process of sternum and costal cartilages of rib pairs 5-7
54
Trapezius
| trunk
= TWO triangular-shaped muscles
- location: the back of the neck in the dorsal trunk
- function: extend the neck, rotate scapulae upward, help adduct scapulae
- origin: occipital bone and vertebrae C1-C7 via the ligamentum nuchae and vertebrae T1-T12
- insertion: acromion and spine of the scapula
55
Other muscles located in between the ribs
| trunk
External Intercostals: pulls ribs upward and outward which occur during INHALATION
- origin: inferior border of upper rib
- insertion: superior border of adjacent lower rib
Internal Intercostals: pulls ribs downward and inward which occur during EXHALATION
- origin: superior border of lower border
- insertion: inferior border of adjacent upper rib
56
Muscles that move the Pectoral Girdle and the Arm
- Deltoid
- Pectoralis Major
- Latissimus Dorsi
- Serratus Anterior
- Other Muscles
57
Deltoid
| pectoral girdle and arm
= resembles an inverted triangle
- location: covers shoulder and causes bulge of upper arm
- function: lateral fibers abduct arm, anterior fibers flex and medially rotate arm, posterior fibers extend and laterally rotate arm
- origin: clavicle and acromion process and spine of scapula
- insertion: deltoid tuberosity of humerus
58
Pectoralis Major
| pectoral girdle and arm
- location: upper chest
- function: adducts and medially rotates the arm, clavicular head flexes arm at shoulder joint, sternocostal head extends arm at shoulder joint
- origin: clavicle, sternum, costal cartilages
- insertion: greater tubercle and intertubercular sulcus of humers
59
```
Latissimus Dorsi (swimmer's muscle)
(pectoral girdle and arm)
```
- location: lower back; laterally and dorsally
- function: extends, adducts and medially rotates arm and draws extended arm backward
- origin: iliac crest and spines of vertebrae T7-12, L1-5, ribs 9-12
- insertion: intertubercular sulcus of humerus
60
Serratus anterior
| pectoral girdle and arm
- location: below axilla; lateral chest
- function: abducts scapula and rotates it upwards, pulls scapula forward around rib cage, helps deltoid muscle raise arm above horizontal level
- origin: upper 9 ribs
- insertion: medial border and inferior angle of scapula
61
other muscles
| (pectoral girdle and arm
Rhomboideus Major, Infraspinatus, Terus Major
62
Muscles that move the Forearm
- Biceps branchii
- Triceps branchii
- Branchialis
- Brachioradialis
63
Biceps branchii
| forearm
- location: anterior arm
- function: flexes forearm at elbow and arm at shoulder, supinates head
- origin: scapula
long head = supraglenoid tubercle-above glenoid cavity
short head = coracoid process
64
Triceps branchii
| forearm
- location: posterior arm
- function: extends forearm at elbow, extends arm at shoulder
- origin:
long head = infraglenoid tubercle of scapula
lateral & medial heads = proximal humerus
- insertion: olecranon process of ulna
65
Brachioradialis
| forearm
- location: lateral forearm
- function: flexes forearm at elbow joint, and draws forearm back to anatomical position following pronation or supination
- origin: lateral distal humerus
- insertion: above styloid process of radius
66
Muscles that move the Hand
- Flexor and Extensor Carpi muscles
| - Flexor and Extensor Digitorum muscles
67
Flexor and Extensor CARPI muscles
| hand
- location: flexors=anterior, extensors=posterior
- function: move hand
- origin: humerus or humerus AND ulna
- insertion: carpals and metacarpals
68
Flexor and Extensor DIGITORUM muscles
- location: flexors=anterior, extensors=posterior
- function: move fingers, flexingor extending a phalanx at MCP, PIP or DIP joints
- origin: humerus or humerus radius AND/OR ulna
- insertion: phalanges
69
Muscles that move the Thigh
- Iliopsoas
- Gluteus maximus
- Gluteus medius
- Adductor muscles
70
Iliopsoas
| thigh
= psoas major and iliacus
- location: lumbar spine and upper thigh
- function: flexes thigh at hip, helps prevent trunk from falling backward in standing position, laterally rotates thigh at hip
- origin: lumbar vertebrae, ilium and sacrum
- insertion: lesser trochanter of the femur
71
Gluteus maximus
| thigh
- location: largest part of buttock
- function: extends and laterally rotates thigh at hip joint
- origin: iliac crest, posterior ilium, sacrum and coccyx
- insertion: proximal femur
72
Gluteus medius
| thigh
- location: partially covered by gluteus maximus
- function: abducts and medially rotates thigh at hip
- origin: ilium
- insertion: greater trochanter
73
Gluteus maximus
- the antagonist of the ileus muscle with respect of extension
- important for running, walking, and climbing the stairs
74
Adductor muscles
| thigh
- pectineus, adductor longus, adductor magnus, adductor brevis and gracilis
75
Adductor muscles
| thigh
- location: medial thigh
- function: adduct, flex and rotate thigh at hip joint
(except POSTERIOR part of adductor magnus extends
thigh at hip)
GRACILIS = flexes leg at knee
- origin: pubis and ischium
- insertion: femur, tibia for GRACILIS
76
Muscles that move the Leg
- Quadriceps femur group
- Hamstring group
- Sartorius
77
Sartorius
| leg
- location: begins posterior-anterior at iliac spine and passes across thigh to medial side of knee and onto the leg
- function: flexes, abducts and laterally rotates the thigh at hip, flexes leg at knee
- origin: anterior superior spine of ilium
- insertion: medial tibial shaft
78
biceps femoris, semimembranosus, semitendinosus
Hamstring group
| leg
79
Hamstring group
| leg
- location: posterior thigh
- function: flex leg at knee, extend thigh at hip
- origin: ischial tiberosity
- insertion: lateral or medial tibia, AND proximal fibula for biceps femoris ONLY
80
rectus femoris, vastus lateralis, vastus intermedius
Quadriceps femoris
| thigh
81
Quadriceps femoris
| thigh
- location: anterior, lateral and medial thigh
- function: extend leg at knee, AND flexes thigh at hip (rectus femoris ONLY)
- origin: rectus femoris = anterior inferior iliac spine
vastus muscles = proximal femur
- insertion: patella
quadriceps tendon continues as patellar ligament to insert on tibial tuberosity
82
Muscles that move the Foot
- Gastrocnemius
- Soleus
- Tibialis Anterior
- Fibularis
- Flexor and Extensor Digitorum muscles
83
Gastrocnemius
| foot
- location: posterior leg (calves)
- function: plantar flexes foot at ankle, flexes leg at knee joint
- origin: lateral and medial condyles of distal femur
- insertion: calcaneus
84
Soleus
| foot
- location: below gastrocnemius
- function: plantar flexes foot at ankle
- origin: proximal medial tibia and head of fibula
- insertion: calcaneus via calcaneum tendon
85
Tibialis anterior
| foot
- location: anterior leg
- function: dorsiflexes foot at ankle, supinates foot at intertarsal joints
- origin: lateral condyle and shaft of proximal tibia, and interosseous membrane
- insertion: 1st cuneiform and 1st metatarsal bones
86
fibularis longus and fibularis brevis
Fibularis also known as Peroneus
87
Fibularis
| foot
- location: lateral leg
- function: plantar flexion of foot at ankle joints, pronation of foot at intertarsal joints
- origin: fibular head and shaft
- insertion: fibularis longus = 1st cuneiform and 1st
metatarsal bones
fibularis brevis = 5th metatarsalbase
88
Flexor and Extensor Digitorum muscles
- location: lateral and posterior leg
- function: plantar flex (flexors) OR dorsiflex (extensors) foot at ankle, flex (flexors) OR extend (extensors) toes in MCP, PIP or DIP
- origin: tibia, fibula and interosseous membrane
- insertion: proximal, middle and distal phalanges
89
adduct
a muscle move a limb or other part of the body toward the midline of the body or toward another part
90
abduct
a muscle move a limb or part away from the midline of the body or from another part.
