Muscular System Anatomy and Functions

Comprehensive vocabulary flashcards covering the names, actions, and key anatomical terms of skeletal muscles of the head, neck, torso, upper limbs, and lower limbs.

Orbicularis oculi

Closes eyes

Zygomaticus

Raises corners of mouth (smiling)

Risorius

Draws corners of mouth laterally ("white person smile")

Epicranius (frontal belly); AKA Frontalis

Elevates eyebrows (surprised)

Corrugator supercilia

Draws eyebrows medially and inferiorly (angry)

Orbicularis oris

Closes lips in a pucker (kissing, whistling)

Depressor anguli oris

Depresses corners of mouth (frowning)

Mentalis

Wrinkles chin (pout)

Platysma

Tenses skin of neck (e.g. during shaving)

Buccinator

Compresses cheek (whistling, sucking)

Temporalis

Closes jaw

Masseter

Closes jaw

Sternocleidomastoid

Flexes and laterally rotates the head

Diaphragm

Inspiration

Intercostals (external and internal)

Elevates and depresses thoracic cage

Quadratus lumborum

Flexes vertebral column laterally

Transversus abdominis (deepest layer)

Compresses abdomen

Rectus abdominis (6 pack)

Flex and rotate lumbar region

Internal oblique

Flex vertebral column, compress abdomen, and trunk rotation and lateral flexion

External oblique (Top/superficial layer)

Flex vertebral column, compress abdomen, and trunk rotation and lateral flexion

Trapezius

Stabilizes, elevates, retracts, and rotates scapula ("shrugging shoulders"); extends head

Rhomboids (major and minor)

Stabilize scapula ("squaring shoulders")

Levator scapulae

Elevates and adducts scapula

Serratus anterior

Rotates scapula upward; pushing, punching, "boxer's muscle"

Supraspinatus (rotator cuff) ANTERIOR

Abduction of arm; stabilizes shoulder joint

Infraspinatus (rotator cuff) ANTERIOR

Laterally rotates arm; stabilizes shoulder joint

Teres minor (rotator cuff) POSTERIOR

Laterally rotates arm; stabilizes shoulder joint

Subscapularis (rotator cuff) POSTERIOR

Medially rotates arm; stabilizes shoulder joint

Deltoid

Prime mover of arm abduction

Pectoralis major

Prime mover of arm flexion; rotates arm medially; adducts arm

Latissimus dorsi

Prime mover of arm extension; adduction and medial rotation of arm (swimming, chin-ups)

Teres major

Extends, medially rotates, and adducts the arm

Biceps brachii

Flexes and supinates forearm

Triceps brachii

Powerful forearm extensor

Brachioradialis

Synergist in forearm flexion

Pronator teres

Pronates forearm

Supinator

Assists biceps brachii to forcibly supinate forearm

Flexor digitorum superficialis

Flexes hand and middle phalanges of fingers 2 thru 5

Flexor carpi radialis

Powerful flexor of hand

Extensor digitorum

Prime mover of finger extension

Extensor carpi radialis longus

Extends and abducts hand

Gluteus maximus

Major extensor of thigh (climbing, running)

Gluteus medius

Abducts and medially rotates thigh (walking)

Biceps femoris (hamstring)

Extends thigh and flexes leg

Semitendinosus (hamstring)

Extends thigh and flexes leg

Semimembranosus (hamstring)

Extends thigh and flexes leg

Pectineus

Adducts, flexes, and medially rotates thigh

Adductors (Adductor longus, adductor brevis, and adductor magnus)

Adducts, flexes, and medially rotates thigh

Gracilis

Adducts, flexes, and medially rotates thigh

Sartorius

Abducts, flexes, and laterally rotates thigh (cross-legged sitting)

Rectus femoris (quadriceps femoris)

Extends leg and flexes thigh

Vastus lateralis (quadriceps femoris)

Extends leg and stabilizes knee

Vastus medialis (quadriceps femoris)

Extends leg

Vastus intermedius (quadriceps femoris)

Extends leg

Fibularis (peroneus) longus

Plantar flexes and everts foot

Tibialis anterior

Prime mover of dorsiflexion and inverts foot

Extensor digitorum longus

Prime mover of toe extension and dorsiflexes foot

Flexor digitorum longus

Plantar flexes and inverts foot; flexes toes (helps foot "grip" the ground)

Soleus (triceps surae)

Plantar flexes foot (postural muscle for walking, running, and dancing)

Gastrocnemius (triceps surae)

Plantar flexes foot

Mastication

The act of chewing

SITS

Mnemonic for the four rotator cuff muscles: supraspinatus, infraspinatus, teres minor, and subscapularis

Pes anserinus

Insertion on the medial tibia formed by the conjoined tendons of the gracilis, sartorius, and semitendinosus

Tendocalcaneus (Achilles tendon)

Common tendon of insertion onto the calcaneus for the gastrocnemius and soleus