Lab Exam 3

Buccinator

Movement: Sucking in cheeks (sucking, blowing)

Epicranial aponeurosis (connective tissue, not a muscle)

Movement: Raises Eyebrows

Frontalis

Action: Raises eyebrows, wrinkles forehead

Masseter

Origin: Zygomatic arch

Insertion: Mandible (angle and ramus)

Action: Elevates mandible (closes jaw)

Mentalis

Nasalis

Occipitalis

Orbicularis Oculi

Action: Closes eyelids (Squint, Squeeze eye shut)

Orbicularis Oris

Action: Puckers lips ("kissing" muscle)

Platysma

Risorius

Action: Draws corner of mouth laterally (smile)

Sternocleidomastoid

Origin: Sternum and clavicle

Insertion: Mastoid process of temporal bone

Action: Rotates head, flexes neck

Temporalis

Origin: Temporal bone

Insertion: Coronoid process of mandible

Action: Elevates and retracts mandible

Zygomaticus major

Action: Elevates corners of mouth (smiling)

Zygomaticus minor

Action: Elevates upper lip (smile/snarl)

Erector spinae group

Action: Straightens Spine

External intercostals

Action: Elevates ribs (Inhalation)

Internal intercostals

Action: Depresses ribs (forced exhale, brings adjacent ribs together)

Diaphragm

Action: Inhalation (flattens to enlarge thoracic cavity)

External obliques

Action: Compress abdomen, flex/rotate trunk

Internal obliques

Action: Compress abdomen, flex/rotate trunk

Rectus abdominis

Origin: Pubic symphysis

Insertion: Xiphoid process, true ribs

Action: Flexes trunk at waist

Transverse abdominis

Action: Rotates Trunk

Trapezius

Action: Elevates shoulders, lateral flexion of head, extends neck

Rhomboid major

Rhomboid minor

Deltoid

Origin: Clavicle and scapula

Insertion: Deltoid tuberosity of humerus

Action: Abducts arm at shoulder

Pectoralis major

Origin: Sternum and clavicle

Insertion: Greater tubercle of humerus

Action: Adducts and medially rotates arm

Latissimus dorsi

Origin: Spinous processes T7-L5

Insertion: Humerus

Action: Adduct arm at shoulder

Levator scapulae

Serratus anterior

Supraspinatus- Rotator Cuff Group (Stabilizes shoulder joint)

Action: Rotate at shoulder

Infraspinatus- Rotator Cuff Group (Stabilizes shoulder joint)

Action: Rotate at shoulder laterally

Subscapularis- Rotator Cuff Group (Stabilizes shoulder joint)

Action: Medially rotates arm

Teres minor- Rotator Cuff Group (Stabilizes shoulder joint)

Action: Laterally rotates arm

Teres major

Pectoralis minor

Origin: Ribs 3-5

Insertion: Coracoid process of scapula

Action: Depresses and protracts scapula

Notes: Deep to pectoralis major.

Biceps brachii

Origin: Scapula

Insertion: Radius

Action: Flexes elbow

Triceps brachii

Origin: Scapula

Insertion: Ulna

Action: Extends elbow

Coracobrachialis

Brachialis

Brachioradialis

Origin: Lateral supracondylar ridge of humerus

Insertion: Styloid process of radius

Action: Flexes elbow

Notes: Forearm muscle visible on lateral side.

Supinator

Action: Supinates forearm (turns palm upward)

Pronator quadratus

Action: Pronates forearm (turns palm down)

Pronator teres

Action: Pronates forearm

Palmaris longus

Flexor carpi ulnaris

Insertion: Anterior Carpals

Action: Flexes wrist

Flexor carpi radialis

Insertion: Anterior Carpals

Action: Flexes wrist

Flexor digitorum superficialis

Insertion: Anterior phalanges

Action: Flexes fingers

Flexor pollicis longus

Insertion: Anterior phalanx 1

Action: Flexes thumb

Extensor carpi ulnaris

Insertion: Posterior Carpals

Action: Extends wrist

Extensor carpi radialis longus

Insertion: Posterior Carpals

Action: Extends wrist

Extensor digitorum

Insertion: Posterior phalanges
Action: Extends fingers

Extensor pollicis

Insertion: Posterior phalanges

Action: Extends thumb

Iliacus (part of lliopsoas group)

Origin: Iliac fossa and sacrum

Insertion: Anterior femur

Action: Hip flexion

Psoas major (part of lliopsoas group)

Origin: Lumbar vertebrae

Insertion: Femur

Action: Hip Flexion

Gracilis

Action: Adducts thigh

Adductor longus

Origin: Pubis

Insertion: Medial femur

Action: Adducts thigh

Adductor magnus

Origin: Pubis

Insertion: Medial femur

Action: Adducts thigh

Gluteus maximus

Origin: Ilium and sacrum

Insertion: Gluteal tuberosity of femur and IT band

Action: Extends, abducts, and laterally rotates thigh

Notes: Largest gluteal muscle.

Gluteus medius

Origin: Ilium

Insertion: Lateral femur

Action: Abducts and medially rotates thigh, Hip extension

Gluteus minimus

Origin: Ilium

Insertion: Lateral femur

Action: Abducts and medially rotates thigh, Hip extension

Tensor fasciae latae (TFL)

Action: Abducts thigh

Iliotibial tract (IT band) (connective tissue)

Sartorius

Popliteus

Biceps femoris

Origin: Ischial tuberosity

Insertion: Fibula
Action: Flexes knee, extends hip

Semitendinosus

Origin: Ischial tuberosity

Insertion: Tibia

Action: Flexes knee, extends hip

Semimembranosus

Origin: Ischial tuberosity

Insertion: Tibia

Action: Flexes knee, extends hip

Rectus femoris

Origin: Ilium

Insertion: Tibial tuberosity via patellar ligament

Action: Extends knee, flexes hip

Vastus lateralis

Origin: Femur

Insertion: Tibial tuberosity via patellar ligament

Action: Extends knee

Vastus medialis

Origin: Femur (linea aspera)

Insertion: Tibial tuberosity via patellar ligament

Action: Extends knee

Vastus intermedius

Origin: Femur

Insertion: Tibial tuberosity via patellar ligament

Action: Extends knee

Tibialis anterior

Action: Dorsiflexion and inversion of foot

Gastrocnemius

Insertion: Calcaneus via Achilles tendon

Action: Plantar flexion (points toes)

Soleus

Insertion: Calcaneus via Achilles tendon

Action: Plantar flexion

Fibularis longus

Action: Plantar flexion and eversion

Fibularis brevis

Action: Plantar flexion and eversion

Tibialis posterior

Action: Plantar flexion and inversion

Flexor digitorum longus

Insertion: phalanges (plantar side)

Action: Flexes toes (curling them downward)

Extensor digitorum longus

Insertion: Phalanges (anterior side)

Action: Extends toes

Agonist

The main muscle responsible for producing a specific movement

Antagonist

The muscle that opposes or reverses the action of the agonist

Synergist

A muscle that helps the agonist in performing its action by adding extra force or reducing unnecessary movement

Fixator

A muscle that stabilizes the origin of the agonist so that it can act efficiently

Flexion

Decreasing the angle between two bones at a joint

Extension

Increasing the angle between two bones

Hyperextension

Extension beyond anatomical position

Adduction

Moving a limb toward the body’s midline

Abduction

Moving a limb away from the body’s midline

Circumduction

Circular movement combing flexion, extension, abduction, and adduction

Supination

Turning palm upward

Pronation

Turning Palm downward

Rotation (medial)

Turning bone toward the body’s midline

Rotation (lateral)

Turning bone away from the body’s midline

Protraction

Moving a body part forward

Retraction

Moving a body part backwards

Elevation

Lifting a body part upward

Depression

Lifting a body part downward

Dorsiflexion

Bringing toes upward toward shin