Muscles to know

Question 1

Occipital frontalis- a

Answer 1

action: raises eyebrow, fixes aponeurosis, pulls scalp posteriorly

Question 2

zygomaticus- all

Answer 2

origin: zygomatic bone
insertion: skin and mouth at corner of mouth
action: raises lateral comers of mouth upward

Question 3

orbicularis oris-a

Answer 3

closes lips; purses and protrudes (kissing and whistling muscle)

Question 4

mentalis-a

Answer 4

protrudes lower lip; wrinkles chin

Question 5

platysma-a

Answer 5

tenses skin of neck

Question 6

masseter-all

Answer 6

origin: zygomatic arch and zygomatic bone
insertion: angle and ramus of mandible
action: prime mover of jaw closure

Question 7

temporalis- all

Answer 7

origin: temporalis fossa
insertion: coronoid process
action: closes jaw; elevates and retracts mandible

Question 8

sternocleidomastoid-all

Answer 8

origin: manubrium of sternum and medial portion of clavicle
insertion: mastoid process of temporal bone and occipital bone
action: flexion of the neck; laterally rotates the head

Question 9

external intercostals- all

Answer 9

origin: inferior border of rib cage
insertion: superior border of rib below
action: pulls rib toward one another to elevate rip cage

Question 10

internal intercostals- all

Answer 10

origin: superior border of rib below
insertion: inferior border of rib above
action: draw ribs together to depress rib cage

Question 11

diaphragm-a

Answer 11

action: prime mover of inspiration flattens on contraction

Question 12

external oblique- a

Answer 12

action: flexes vertebral column; compresses abdominal wall; aids. in trunk rotation and lateral flexion

Question 13

internal oblique-a

Answer 13

action: flexes vertebral column; compresses abdominal wall; aids. in trunk rotation and lateral flexion

Question 14

transverse abdominis- a

Answer 14

action: compresses abdominal contents

Question 15

rectus abdominis- a

Answer 15

action: flexes vertebral column

Question 16

pectoralis major- all

Answer 16

origin: clavicle, sternum, cartilage of ribs 1-6
insertion: intertubercular sulcus of humerus
action: prime mover of arm flexion; adducts, medially rotates arm

Question 17

Serratus anterior- a

Answer 17

action: prime mover to protract and hold scapula against chest wall; rotates scapula

Question 18

trapezius- a

Answer 18

action: raises rotates, and adducts scapula and stabilizes it

Question 19

levitator scapula- all

Answer 19

origin: transverse processes (of C1-C4)
insertion: medial border of scapula (superior to spine)
action: elevates and abducts scapula

Question 20

rhomboids- all

Answer 20

origin: spinous process (of C7-T5)
insertion: medial border of scapula
action: stabilizes scapula

Question 21

pectoralis major- all

Answer 21

origin: clavicle, sternum, cartilage of ribs 1-6
insertion: intertubercular sulcus of humerus
action: prime mover of arm flexion; adducts and medially rotates arm

Question 22

deltoid- all

Answer 22

origin: lateral 1/3 of clavicle; acromion and spine of scapula
insertion: deltoid tuberosity of humerus
action: prime mover of arm abduction

Question 23

latissimus dorsi- a & i

Answer 23

insertion: intertubercular sulcus of humerus
action: prime mover of arm extension; adducts and medially rotates arm

Question 24

teres major-all

Answer 24

origin: posterior surface at inferior angle of scapula
insertion: intertubercular sulcus of humerus
action: extends, medially rotates, and adducts arm

Question 25

subscapularis- all

Answer 25

origin: subscapular fossa of scapula insertion: lesser tubercular of humerus action: medially rotates arm

Question 26

supraspinous- all

Answer 26

origin: supraspinous fossa of scapula insertion: greater tubercle of humerus action: initiates abduction of the arm

Question 27

infraspinous- all

Answer 27

origin: infraspinous fossa of scapula insertion: greater tubercle of humerus action: lateral rotation of arm

Question 28

teres minor- all

Answer 28

origin: lateral border of dorsal scapular surface insertion: greater tubercle of humerus action: lateral rotation of arm

Question 29

triceps brachii- a & i

Answer 29

insertion: olecranon of ulna action: powerful forearm extensor

Question 30

bicep brachii- a & i

Answer 30

insertion: radial tuberosity action: flexes and supinates forearm

Question 31

Flexors of the forearm/wrist- o & i

Answer 31

origin: most on medial epicondyle of humerus action: flexes forearm

Question 32

Extensors of the forearm/wrist- o & a

Answer 32

origin: most on lateral epicondyle of humerus action: extends forearm

Question 33

Iliopsoas→ iliacus and psoas major- a

Answer 33

action: flex trunk at hip joint, flex thigh; lateral flexion of vertebral column

Question 34

Tensor fasciae latae- a

Answer 34

action: steadies trunk

Question 35

sartorius- all

Answer 35

origin: ASIS insertion: medial tibia action: flexes, abducts, and laterally rotates thigh; flexes leg

Question 36

Quadriceps femoris→ rectus femoris, vastus lateralis, vastus medialis, vastus intermedius- all

Answer 36

origin: rectus femoris on ASIS; the rest on proximal femur insertion: tibial tuberosity and patella action: extends leg; rectus femoris flexes thigh*

Question 37

gracilis- a

Answer 37

action: adducts thigh; flexes and medially rotates leg

Question 38

adductors of thigh- a

Answer 38

action: adduct and medially rotate and flex thigh

Question 39

Gluteus maximus- all

Answer 39

origin: ilium, sacrum, coccyx insertion: gluteal tuberosity of femur action: powerful thigh extensor

Question 40

Gluteus medius- all

Answer 40

origin: ilium insertion: greater trochanter of femur action: abducts and medially rotates thigh

Question 41

Gluteus minimus- all

Answer 41

origin: ilium insertion: greater trochanter of femur action: abducts and medially rotates thigh

Question 42

Hamstrings→ biceps femoris, semitendinosus, semimembranosus- o & a

Answer 42

origin: ischial tuberosity action: extends thigh; flexes leg

Question 43

tibialis anterior- a

Answer 43

action: prime mover of dorsiflexion

Question 44

gastrocnemius- a

Answer 44

action: plantar flexes foot

Question 45

soleus- a

Answer 45

action: plantar flexion