Muscle Identification Part 1 Days 1,2,3 Temporalis Origin: Temporal Bone Insertion: mandible Action: close jaw (bite) Orbicularis Oculi Origin: Frontal and maxilla bones Insertion: eyelid skin and fascia Action: blink, squint, etc Orbicularis Oris Origin: maxilla and mandible Insertion: skin and muscles around lips Action: moves lips (kissing muscle) Depressor anguli oris Origin: mandible below lateral incisors Insertion: corner of mouth Action: frowning Buccinator Origin: molar region of maxilla and mandible Insertion: side of mouth Action: pulls corners of mouth laterally and compresses cheeks (whistling muscle) Zygomaticus major Origin: anterior zygomatic arch Insertion: corner of mouth Action: smile Masseter Origin: posterior zygomatic bone and temporal bone Insertion: ramus of mandible Action: close jaw (Bite) Rhomboideus major Origin: spinous processes of vertebrae T2 T5 Insertion: inferior medial border of scapula Action: retracts scapula and rotates it downwards Pectoralis minor Origin: ventral side of ribs 3 5 Insertion: coracoid process of scapula Action: pulls shoulders forward and down Levator scapulae Origin: Transverse processes of vertebrae C1 C4 Insertion: superior medial border of scapula Action: elevates scapula (shoulders); shrugs (I dont know muscle) Latissimus dorsi Origin: vertebrae T9 T 12 and iliac crest Insertion: proximal ventral humerus Action: pulls arms back (extensor of arms) Pectoralis major Origin: upper abdominal aponeurosis, sternum and medial part of clavicle Insertion: proximal ventral humerus Action: adducts arms and shoulders Trapezius Origin: vertebrae T12 all the way up to occipital bone Insertion: scapula spine, shoulder, lateral clavicle Action: extends neck and adducts scapula (pulls it medially)