MAJOR Skeletal Muscles of the Human Body. FRONTALIS.

MAJOR Skeletal Muscles

of the Human Body

FRONTALIS

Raises forehead & eyebrows;

wrinkles forehead (horizontally)

MASSETER

Elevates mandible

TEMPORALIS

Closes jaw elevates and retracts

mandible(as in chewing)

ORBICULARISOCULI

Shopw Blinking, squinting,

and draws eyebrows inferiorly

LJKLJKKLJKLJK

ORBICULARIS ORIS

Closes lips; purses and protrudes

lips; kissing & whistling muscle

BUCCINATOR

Draws corners of mouth laterally;

compresses cheek when

sucking/whistling; holds food between teeth when chewing

ZYGOMATICUS

Smiling muscle; raises lateral corners

of mouth upward

STERNOCLEIDO-MASTOID

Flexes head; helps lift head

when lying down; tilts head to side

SPLENIUS

Together: extend/hyperextend

the head; Separate:

Rotate and tilt head to one side

TRAPEZIUS

Elevates, retracts,

depresses and rotates shoulder

LATISSIMUSDORSI

Extends & adducts arm; depresses shoulder; allows

movements such as striking,

hammering, swimming,

rowing, pull-up

DELTOID

Abducts arm; swings arms while walking

PECTORALISMAJOR

Flexes arm; adducts arm against

resistance; pulls ribcage upward; allows movements for

climbing, throwing, pushing, and forced

inhaling

BICEPS BRACHII

Flexes elbow joint; supinates forearm

Example: open a bottle of wine,

turn the corkscrew and pull cork

TRICEPSBRACHII

Extends forearm with or without

resistance;reaching

RECTUS ABDOMINUS

Flex and rotate lumbar region; stabilize pelvis during walking

EXTERNAL OBLIQUE

Together:Help rectus abdominus to flex vertebral column

(bending over/back)

Separate:Help to rotate trunk and

lateral flexion

GLUTEUS MAXIMUS

Extends thigh; when thigh is flexed,

helps us to climb stairs or run;

laterally rotates and abducts thigh

RECTUS FEMORIS

Extends knee and

flexes thigh at hip

GRACILIS

Adducts thigh; flexes and medially

rotates thigh; flexes knee

SARTORIUS

Flexes, abducts, and laterally rotates thigh;

“tailor’s muscle” = sitting cross-legged

BICEPS FEMORIS

Extends thigh and flexes knee;

laterally rotates leg

GASTROCNEMIUS

Plantar flexes foot when knee is

extended

TIBIALIS ANTERIOR

Dorsiflexion of foot; inverts foot

FIBULARISLONGIS

Ghgfhgfh

Sfs

Plantar flexes and everts foot; helps keep flat foot

on ground