Transcript Document
Lab Activity 11: Group I Muscles Martini Chapter 11 Portland Community College BI 231 Origin and Insertion • Origin: The place where the fixed end attaches to a bone, cartilage, or connective tissue. • Insertion: The site where the movable end attaches to another structure. 2 MUSCLES OF THE HEAD Frontalis Epicranial Aponeurosis • Origin: Epicranial aponeurosis • Insertion: Skin over forehead • Action: Elevates eyebrows and wrinkles skin of forehead 4 Occipitalis • Origin: Occipital and temporal bones • Insertion: Epicranial aponeurosis • Action: Fixes epicranial aponeurosis and pulls scalp posteriorly 5 Orbicularis Oculi • Origin: Medial orbital margin and zygomatic bone • Insertion: Skin surrounding eye • Action: Closes eyelids and depresses skin of forehead 6 Temporalis • Origin: Temporal fossa • Insertion: Coronoid process of mandible • Action: Elevates and retracts mandible 7 Masseter • Origin: Zygomatic process and arch • Insertion: Angle and ramus of mandible • Action: Elevates mandible 8 Orbicularis Oris • Origin: By muscular skips to surround muscles • Insertion: Muscles interlace to surround mouth • Action: Closes and purses lips 9 Zygomaticus Major • Origin: Zygomatic arch • Insertion: Corner of mouth • Action: Elevates corner of mouth 10 Sternohyoid • Origin: Posterior surface of manubrium, and medial clavicle • Insertion: Hyoid bone • Action: Depresses hyoid bone 11 Sternocleidomastoid • Origin: Manubrium and medial third of clavicle • Insertion: Mastoid process • Action: Rotates head to opposite side, extends head, and flexes vertebral column 12 Trapezius • Origin: External occipital protuberance, superior nuchal line and spinous process of C7-T12 • Insertion: Anterior border of scapular spine, acromion process, lateral third of clavicle • Action: Elevates, adducts, and depresses scapula 13 Latissimus Dorsi • Origin: Spinous processes of lower 6 thoracic vertebrae, thoracolumbar fascia, crest of ilium • Insertion: Intertubercular groove of humerus • Action: Extends, rotates humerus medially, draws shoulder down and backward 14 Levator Scapula • Origin: Transverse processes of C1-4 • Insertion: Superior angle spine of scapula • Action: Elevates scapula 15 Rhomboid Major • Origin: Spinous process of T1-5 and supraspinous ligament • Insertion: Medial border below spine of scapula • Action: Adducts scapula and performs downward rotation 16 Rhomboid Minor • Origin: Spinous process of C7-T1 • Insertion: Medial border of scapula at base of spine • Action: Adducts scapula and performs downward rotation 17 Serratus Anterior • Origin: Lateral surface of upper 8 ribs • Insertion: Anterior lip of medial border of scapula • Action: Holds scapula to chest wall, medially rotates scapula in abducting or extending humerus 18 Erector Spinae • Origin: Sacrum, iliac crest, spinous processes of lumbar vertebrae and T11,12 • Insertion: Angles of the ribs. Spinous & Transverse processes of vertebrae • Action: Extension of vertebral column 19 Scalenes Anterior • Origin: Transverse processes of C3-C6 • Insertion: 1st rib • Action: Elevates 1st rib, flexes neck forward and laterally, rotates neck 20 Scalenes Middle • Origin: Transverse processes of C2-C7 • Insertion: 1st rib • Action: Elevates 1st rib, flexes neck forward and laterally, rotates neck 21 Scalenes Posterior • Origin: Transverse processes of C4-C6 • Insertion: 2nd rib • Action: Elevates 2nd rib, flexes neck laterally, slightly rotates neck 22 External Intercostal • Origin: Inferior border of rib above • Insertion: Superior border of rib below • Action: Elevates rib cage during inspiration 23 Internal Intercostal • Origin: Superior border of rib below • Insertion: Inferior border of rib above • Action: Depresses rib cage during expiration 24 Pectoralis Major • Origin: Medial half of clavicle, sternum, costal cartilages, aponeurosis of external abdominal oblique • Insertion: Intertubular groove of humerus • Action: Flexes, adducts, and medially rotates humerus, draws body upward in climbing 25 Pectoralis Minor • Origin: Anterior surface of ribs 3 to 5 • Insertion: Coracoid process of scapula • Action: Draws scapula down and forward and elevates ribs 26 Rectus Abdominus • Origin: Pubis symphysis and crest of pubis • Insertion: Xiphoid process and cartilages of ribs 5 to 7 • Action: Tenses abdominal wall and flexes vertebral column 27 External Abdominal Oblique • Origin: External surface of lower 8 ribs • Insertion: Anterior half of iliac crest and linea alba • Action: Compresses abdomen, contralaterally rotates and flexes vertebral column 28 Internal Abdominal Oblique • Origin: Lateral half of inguinal ligament, anterior iliac crest and thoracolumbar fascia • Insertion: Lower four ribs, linea alba and by conjoined tendon to pubis • Action: Compresses abdomen, ipsilaterally rotates and flexes vertebral column 29 Transverse Abdominis • Origin: Lateral third of inguinal ligament, anterior iliac crest, and thoracolumbar fascia • Insertion: Linea alba, and by conjoined tendon to pubis • Action: Compresses abdomen 30 The End 31