Muscle Origins and Insertions - Set 1

1.Origin: Margin of orbit
Insertion: Eyelid and skin of face
Action: Closes eye; blink
2.Origin: Maxilla and mandible
Insertion: Skin of lips
Action: Purses lips
3.Origin: Zygomatic bone
Insertion: Mandible
Action: Elevates mandible; mastication
4.Origin: Manubrium and clavicle
Insertion: Mastoid process of temporal bone
Action: Bilateral contraction flexes head at neck; Unilateral contraction bends neck towards shoulder or laterally rotates head
5.Origin: Inferior clavicle and fascia of chest
Insertion: Inferior surface of mandible
Action: Draws corners of mouth inferiorly and tenses skin of neck by drawing it superiorly
6.Origin: Inferior border of superior rib
Insertion: Superior border of inferior rib
Action: Elevates ribs
7.Origin: Superior boarder of inferior rib
Insertion: Inferior boarder of superior rib
Action: Depresses ribs
8.Origin: Inferior border of rib cage (Inferior costal aperture)
Insertion: Central tendon
Action: Contraction increases intra-thoracic space thereby decreasing intra-thoracic pressure
9.Origin: External, inferior borders of ribs
Insertion: Linea alba and iliac crest
Action: Flexes spine at the hip; compresses abdomen
10.Origin: Pubic bone (pubis)
Insertion: Costal cartilages and xiphoid process
Action: Flexes spine at the hip; compresses abdomen