muscles of upper body

Frontalis

Action: elevates the eyebrows and wrinkles forehead

Occipitalis

Action: pulls scalp posteriorly

Orbicularis oculi

Action: closes eye, winking, blinking

Orbicularis oris

Action: Purse lips, puckered lips

Masseter

Action: elevates the mandible, prime mover of jaw closure

Sternocleidomastoid

Action: if both pair contracts it causes flexion of neck forward; rotates/pivots head to opposite side

Temporalis

action: closes jaw

Platysma

action: tenses skin of the neck and draws the corners of the mouth down

Diaphragm

Action: when it contracts it flattens; action is in inspiration and compresses abdominal contents

pectoralis minor

action: pulls the coracoid process and pulls scapula down

Pectoralis major

Action: prime mover of arm flexion, adducts, medially rotates arm

Trapezius

Action: extends head

Latissimus dorsi

Action: extends the arm and rotates the arm

medially

Deltoid

Action: middle fibers abducts arm,

anterior fibers flex and medially

rotate the arm, posterior fibers

extend and externally rotate the

humerus

Supraspinatus

Action: abducts the arm (initiates

abduction)

Infraspinatus

Action: laterally rotates the arm

Subscapularis

Action: medially rotates the arm, assists in extension of the arm

Transversus abdominis

Action: compresses abdominal contents

external intercostals

action: elevate rib cage

Internal intercostals

draw ribs together to depress rib cage, aid in expiration

Serratus anterior

prime mover to protract and hold scapula against chest wall, rotates scapula

Rectus abdominus

External oblique

Triceps brachii(lateral and medial)

Action: extension of the elbow

Biceps brachii(long and short)

Action: flexion of elbow

Brachialis

Action: flexion of elbow

Brachioradialis

Action: flexion of the elbow

Pronator teres

Action: pronates the forearm

Flexor carpi radialis

Action: flexion of the wrist and abduction

Palmaris longus

Action: help tighten skin on palm, aids in flexion of the wrist

Flexor carpi ulnaris

Action: flexion of the wrist and adduction

Flexor digitorum superficialis

Action: flexion of wrist

Extensor carpi radialis longus

Action: extends and abducts wrist

Extensor carpi radialis brevis

Action: extends and abducts wrist

Extensor digitorum

Action: extension of fingers and wrist

Extensor carpi ulnaris

Action: extends the wrist

Extensor pollis longus

Actoin: extends thumb

Abductor pollis longus

Action: abducts the thumb