Texas A&M Biol 319 Lab 4 AOIs

Obliques (external and internal)

Action: compression of abdomen, flexion and rotation of trunk

Origin: ribs (external), iliac crest (internal)

Insertion: iliac crest (external), ribs (internal)

HUMANS AND CATS

Transverse abdominis

Action: compression of abdomen

Origin: ribs and iliac crest

Insertion: Linea alba

HUMAN

Rectus abdominis

Action: flexion of trunk; compression of abdominal wall

Orgin: pubic crest

Insertion: xiphoid process and ribs 5-7

HUMANS AND CATS

Intercoastals (external and internal)

Action: elevation and depression of ribs

Orgin: superior border of ribs (external); inferior border of ribs (internal)

Insertion: inferior border of ribs (external); superior border of ribs (internal)

HUMANS AND CATS

Diaphragm

Action: opens thoracic cavity for lungs during inspiration

Orgin: ribs 5-10 and lumbar vertebrae

Insertion: central tendon

HUMAN

Frontails

Action: raises eyebrows

Orgin: epicranial aponeurosis

Insertion: skin of eyebrows and root of nose

HUMAN

Occipitalis

Action: pulls scalp posteriorly

Orgin: occipital bone

Insertion: epicranial aponeurosis

HUMAN

Temporalis

Action: closes jaw; retracts mandible

Orgin: temporal fossa

Insertion: coronoid process (mandible)

HUMAN

Masseter

Action: closes jaw

Orgin: zygomatic arch

Insertion: angle and ramus (mandible)

HUMANS AND CATS

Zygomaticus

Action: elevates corners of mouth

Orgin: zygomatic bone

Insertion: corner of mouth

HUMAN

Buccinator

Action: compression of cheek

Orgin: molar region (maxilla and mandible)

Insertion: orbicularis oris

HUMAN

Platysma

Action: tenses skin of neck; depression of lower lip

Orgin: fascia of chest

Insertion: mandible and corner of mouth

HUMAN

Orbicularis oculi

Action: closes eyes

Orgin: frontal bone and maxilla

Insertion: eyelids

HUMAN

Orbicularis oris

Action: closes and protrudes lips

Orgin: maxilla and mandible

Insertion: angles of mouth

HUMAN

Levator labii superioris

Action: elevation of upper lip

Orgin: zygomatic bone and infraorbital margin (maxilla)

Insertion: upper lip

HUMANS

Depressor labii superioris

Action: depression of lower lip

Orgin: body of mandible

Insertion: lower lip

HUMAN

Sternocleidomastoid

Action: flexion and rotation of neck

Orgin: manubrium and clavicle

Insertion: mastoid process (temporal bone)

HUMANS AND CATS

scalenes

Action: elevation of ribs 1 & 2; rotation of neck

Orgin: transverse processes of cervical vertebrae C3-C7

Insertion: ribs 1-2

HUMANS AND CATS

serratus anterior

Action: abduction and rotation of scapula

Orgin: true ribs

Insertion: medial border (scapula)

HUMANS AND CATS

rhomboids

Action: adduction and elevation of scapula

Orgin: spinous processes of vertebrae C7-T5

Insertion: medial border (scapula)

HUMANS AND CATS

splenius

Action: rotation of head; extension of neck

Orgin: spinous process of vertebrae C7-T6

Insertion: temporal and occipital bone

HUMANS AND CATS

digastric

Action: elevation of hyoid; opens mouth

Orgin: lower margin (mandible); mastoid process (temporal bone)

Insertion: hyoid bone

HUMANS AND CATS

mylohyoid

Action: elevation of hyoid and floor of mouth

Orgin: medial surface (mandible)

Insertion: hyoid bone

HUMANS AND CATS

geniohyoid

Action: elevation and protraction of hyoid bone

Orgin: mental tubercule

Insertion: hyoid bone

HUMANS AND CATS

sternothyroid

Action: depression of hyoid and larynx

Orgin: manubrium (sternum)

Insertion: thyroid cartilage

HUMANS AND CATS

thyrohyoid

Action: depression of hyoid; elevation of larynx

Orgin: thyroid cartilage

Insertion: hyoid bone

HUMANS AND CATS