Muscular System

“Anterior muscle attachments & Actions”

“Origin and insertion" Origin – where the fixed (non-moving) end of the muscle attaches to the bone (cartilage or connective tissue) Insertion – where the movable end of the muscle attaches to another structure

Temporalis Origin: Temporal Bone Insertion: Mandible Movement (Action): Closes Jaw (chew)

Orbicularis Oculi Origin: Frontal Bone and Maxilla Insertion: Tissue around the eye Movement (Action): Blinks and Closes Eyes

Orbicularis Oris (kissing muscle) Origin: Mandible and Maxilla Insertion: Skin and muscles around the mouth Movement (Action): Closes and protrudes lips (kissing muscle)

Masseter Origin: Zygomatic Bone Insertion: Mandible Movement/Action: closes jaw

zygomaticus Origin: Zygomatic Bone Insertion: skin and muscle at corner of lips Movement/Action: Raises corner of the mouth to smile

Sternocleidomastoid Origin: sternum and clavicle Insertion: mastoid process of temporal bone Movement/Action: flex and laterally rotates neck

Pectoralis major Origin: sternum and clavicle Insertion: humerus Movement: flexes shoulder, medially rotates arm, adducts arm

Pectoralis Minor Origin: 3rd – 5th ribs Insertion: Scapula Movement/Action: stabilizes the scapula against the thoracic wall

Deltoid Origin: clavicle, spine of scapula Insertion: humerus Posterior View Anterior View Origin: clavicle, spine of scapula Insertion: humerus Movement/Action: flexion, abduction, extension of shoulder

Biceps Brachii Origin: scapula Insertion: radius Movement: flexes and supinates forearm

External oblique Origin: lower 8 ribs Insertion: ilium (iliac crest) Movement: flexion at the hips and spine

Insertion: sternum and 5th-7th rib Rectus Abdominis Origin: pubis Insertion: sternum and 5th-7th rib Movement/Action: Flexes vertebral column

Transverse Abdominis Origin: Costal Cartilage, ilium Insertion: Pubic Movement/Action: helps in expiration