Anatomy Muscles Flashcards
epicranius frontal belly
raise eyebrows and wrinkle forehead skin horizontally
epicranius occipital belly
fixes aponeurosis & pulls scalp posteriorly
orbicularis oculi
closes eyes; blinking, squinting, & draws eyebrows inferiorly
zygomaticus major
raises lateral corners of mouth upward (smiling muscles)
orbicularis oris
closes lips; kissing & whistling muscle
platysma
tenses skin of neck; helps depress mandible; pulls back & down, produce downward sag of mouth
masseter
prime mover of jaw closure; elevates mandible
temporalis
closes jaw; elevates & retracts mandible; maintains position of mandible @ rest; deep anterior part may protract mandible
sternocleidomastoid
flexes & laterally rotates the head; rotates head towards shoulder & neck
external intercostals
pulls ribs towards one another to elevate the rib cage
internal intercostals
draw ribs together & depress rib cage
rectus abdominis
flex & rotate lumbar region of vertebral column; fix & depress ribs, stabilize pelvis when walking, used in sit-ups
external oblique
flex vertebral column and compress abdominal wall; aid in trunk rotation & lateral flexion; used in oblique curls
internal oblique
used for external obliques
transversus abdominis
compress abdominal contents
serratus anterior
rotates scapula so that its inferior angle moves laterally upward; holds scapula against chest wall; pushing; punching
trapezius
stabilizes, rotates, raises, & retracts scapula; shrug shoulders, extend head with scapula fixed
levator scapulae
elevates/adducts scapula; tilts glenoid cavity downward when scapula is fixed, flexes neck to same side
rhomboids major
stabilizes scapula; act together to adduct scapula "squaring shoulders"
rhomboids minor
stabilizes scapula; act together to adduct scapula "squaring shoulders"
pectoralis major
prime mover of arm flexion; rotates arm medially; adducts arm; help in climbing, throwing, pushing, & forced inspiration
deltoid
prime mover in arm abduction when all its fibers contract simultaneously; activate during arm swing in rhythm when walking
latissimus dorsi
prime mover in arm extension; powerful arm adductor; medially rotates arm at shoulder; hammer, swim, rowing
subscapularis
chief medial rotator of humerus; holds head of humerus in glenoid cavity, stabilizing shoulder joint
infraspinatus
rotates humerus laterally; helps hold head of humerus in glenoid cavity stabilizing shoulder joint
teres major
extends; medially rotates & adducts humerus; synergist of latissimus dorsi
coracobrachialis
flexion & adduction of humerus; synergist of pectorals major
triceps brachii
powerful forearm extensor against resistance
biceps brachii
flexes elbow joint & supinates forearm
brachialis
major forearm flexor (lifts ulna as bicep lifts radius)
brachioradialis
synergist in forearm flexion; acts best when partially flexed & semipropanated; stabilizes elbow during rapid flexion & tension
pronator teres
pronates forearm; weak flexor of elbow
flexor carpi radialis
(used to take pulse) powerful flexor of wrist; adducts hand; weak synergist of elbow flexion
palmaris longus
tenses skin of fascia palm during hand movements; weak wrist flexor & elbow flexion
flexor carpi ulnaris
powerful flexor of wrist; also adducts hand in concert with extensor carpi ulnaris; stabilizes wrist during finger extension
extensor carpi radialis longus
extends & abducts wrist; acts with extensor carpi radials longus to steady wrist during finger flexion
extensor digitorum
prime mover of finger extension; extends wrist; can abduct (flares) fingers
extensor carpi ulnaris
extends wrist with extensor carpi radials; adducts wrist with flexor carpi ulnaris
sartorius
flexes, abbducts, and laterally rotates thigh; flexes knee, produces cross-legged position
adductor longus
adducts, flexes; and medially rotates thigh
gracilis
adducts thigh; flexes; medially rotates leg; especially during walking
rectus femoris (part of quadriceps femoris)
extends knee & flexes knee at hip
vastus lateralis (part of quadriceps femoris)
extends & stabilizes knee
vastus intermedialis (part of quadriceps femoris)
extends knee
tensor fasciae latae
steadies knee & trunk on thigh by making iliotibial tract taut; flexes & abducts thigh; rotates thigh medially
gluteus maximus
extensor of thigh; used when climbing stairs & running; laterally rotates & abducts thighs
gluteus medius
abducts & medially rotates thigh; steadies pelvis; important in walking, so foot can come off ground
biceps femoris
extends thigh & flexes knee; laterally rotates leg; especially when knee is flexed
semitendinosus
extends thigh & flexes knee with semimembranosus; medially rotates leg
semimembranosus
extends thigh & flexes knee; medially rotates leg
tibialis anterior
prime mover of dorsi flexion; inverts foot; assists in supporting medial longitudinal arch of foot
extensor digitorum longus
prime mover of toe extension (at metatarsophalange joint) dorsi flexes foot
extensor hallucis longus
extends great toe; dorsi flexes foot
fibularis (peroneus) longus
plantar flexes and everts foot; may help kep foot flat on ground
gastrocnemius
plantar flexes foot; flexes knee joint; can flex knee when foot is dorsi flexed
soleus
plantar flexes foot; important in locomotor and postural muscle in walking, running, and dancing
vastus medialis (part of quadriceps femoris)
extends knee