Welcome to Dr. Kate Brilakis' Learning Portal
tensor faciae latae: flexes/abducts thigh
muscles of anterior torso
trapezius: elevates/rotates scapula
pectoralis minor: elevates rib cage
soleus: plantar flexion of foot
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Muscles on the anterior surface of the body are usually involved in FLEXION
Muscles on the posterior surface of the body are usually involved in EXTENSION
Muscles on the medial surface of the body are usually involved in ADDUCTION
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Muscles on the lateral surface of the body are usually involved in ABDUCTION
gluteus maximus: thigh extension
deltoid: shoulder abdunction
levetor scapulae: elevates scapula
tibialis anterior: dorsiflexion of foot
intercostals: elevate/depress ribs during breathing
palmaris longus: flexion of wrist
obliques: rotation of trunk
biceps femoris
semitendinosus
​semimembranosus
muscles of posterior torso
muscle to bone...
origin:
the origin of a muscle is the point where it attaches to a bone that remains stable/immobile during the muscle's action. usually a proximal attachment.
insertion:
the insertion is the point where the muscle attaches to a bone that moves during the muscle's action. usually the distal attachment.
movement:
when a muscle contracts, the insertion pulls the bone it's attached to, bringing it closer to the origin.
pectoralis major: adduction of arm
example:
biceps brachii: the origin is on the scapula
the insertion is on the radius
when the biceps contracts, it pulls the radius closer to the scapula, causing flexion of the elbow
muscles of the arm
agonist muscles
fibularis longus: plantar flexion of foot
muscles of the hip and posterior thigh
fyi: rotator cuff muscles
extensor digitorum: finger extension
frontalis: raises eyebrow wrinkles forehead
tendon
tough, fibrous connective tissue that connects muscle to bone.
antagonist muscles
The Muscular System
triceps brachii: extension at elbow
quadriceps group:
all work as synergists
to extend the knee
orbicularis orisi: closes lips
buccinator: compresses cheeks
flexor carpi radialis: flexes hand
latissimus dorsi: arm extension/rotation
zygomaticus major: elevates corner of mouth
muscles of head
erector spinae muscle group: extend vertebral column
orbicularis oculi: closes eye
hamstring group:
all work as synergists
to flex the knee
biceps brachii: flexion at elbow
temporalis: elevates mandible
masseter: closes jaw
rectus abdominus: flexes trunk
muscles of the lower leg
transverse abdominus: compresses abdomen
gastrocnemius: plantar flexion of foot
muscles of the hip and anterior thigh
sartorius: flexes/abducts thigh
adductor longus: adducts thigh
gracilis: flexes/adducts thigh
deltoid: shoulder abdunction
brachioradialis: synergist w/biceps