Muscle Actions - Easy Study Guide

Vocabulary-style flashcards defining the actions of primary muscles in the human body based on the lecture notes.

Orbicularis oculi

Closes eyes

Orbicularis oris

Closes/puckers lips

Buccinator

Compresses cheek

Zygomaticus major & minor

Raises corners of mouth (smile)

Mentalis

Pouts lower lip / wrinkles chin

Masseter

Closes jaw; bite down.

Temporalis

Closes jaw + pulls jaw backward; bite down + pull back.

Sternocleidomastoid (SCM)

Bends neck forward + turns head to opposite side

External oblique

Compresses abdomen + rotates trunk to opposite side

Internal oblique

Compresses abdomen + rotates trunk to same side

Transverse abdominis

Compresses abdomen

Rectus abdominis

Bends trunk forward + compresses abdomen

Diaphragm

Inhalation/breathe in

External intercostals

Lift ribs -> inhale

Internal intercostals

Lower ribs -> exhale

Trapezius

Shrugs/elevates and retracts scapula

Pectoralis minor

Pulls scapula forward + down

Levator scapulae

Lifts/elevates scapula

Serratus anterior

Pulls scapula forward

Rhomboid major

Pulls scapula backward (retracts)

Biceps femoris

Bends knee + moves thigh backward

Semitendinosus

Bends knee + moves thigh backward

Semimembranosus

Bends knee + moves thigh backward

Rectus femoris

Straightens knee + brings thigh forward

Vastus intermedius

Straightens knee

Vastus lateralis

Straightens knee

Vastus medialis

Straightens knee

Tibialis anterior

Pulls foot UP + turns sole inward

Gastrocnemius

Points toes DOWN + bends knee

Soleus

Points toes DOWN

Extensor digitorum longus

Straightens toes + pulls foot UP

Supraspinatus

Starts arm abduction (arm out to side)

Infraspinatus

Rotates arm outward

Teres minor

Rotates arm outward

Subscapularis

Rotates arm inward

Pectoralis major

Arm forward/toward body + rotates inward

Latissimus dorsi

Arm backward / toward body + rotates inward

Deltoid

Raises arm out to side (abduction)

Biceps brachii

Bends elbow + turns palm upward

Brachialis and Brachioradialis

Bends elbow

Triceps brachii

Straightens elbow

Flexors (group)

Bend/flex wrist and fingers - front of forearm

Extensors (group)

Straighten/extend wrist and fingers - back of forearm

Gluteus maximus

Moves thigh backward + rotates outward

Gluteus medius/minimus

Moves thigh out to side + rotates inward

Tensor fasciae latae

Thigh forward + out to side + rotates inward

Sartorius

Flexes thigh + rotates outward + bends knee

Adductor longus

Pulls thigh inward / toward midline

Gracilis

Pulls thigh inward + bends knee