Axial Muscles

Question 1

Frontal belly of occipitofrontalis

Answer 1

Origin: skin of forehead
Insertion: epicranial aponeurosis
Action: moves scalp and elevates eyebrows

Question 2

Occipital belly of occipitofrontalis

Answer 2

Origin: superior nuchal line
Insertion: epicranial aponeurosis
Action: retracts scalp

Question 3

Obicularis oris

Answer 3

Origin: mandible and maxillae
Insertion: skin and lips around mouth
Action: closes lips, puckers lips

Question 4

Platysma

Answer 4

Origin: fascia of deltoid and pectoral muscles
Insertion: skin of cheek and mandible
Action: pulls lower lips inferiorly, tenses neck

Question 5

Buccinator

Answer 5

Origin: alveolar process of mandible and maxillae
Insertion: obicularis oris
Action: compresses cheek, aids in sucking and blowing

Question 6

Temporalis

Answer 6

Origin: superior and inferior portions of temporal bone
Insertion: coronoid process
Action: elevates and retracts mandible

Question 7

Masseter

Answer 7

Origin: zygomatic arch
Insertion: lateral surface of rammus
Action: elevates and protracts mandible

Question 8

Medial pterygoid

Answer 8

Origin: maxilla, palatine, and medial surface of pterygoid plate
Insertion: medial surface of mandibular rammus
Action: elevates and protracts mandible

Question 9

Lateral pterygoid

Answer 9

Origin: greater wing of sphenoid
Insertion: condylar process of mandible
Action: protracts mandible

Question 10

Anterolateral neck muscle

Answer 10

Origin: manubrium and sternal ends of clavicle
Insertion: mastoid process of temporal bones
Action: head is pulled forward and down

Question 11

Splenius capitis

Answer 11

Origin: ligamentum nuchae
Insertion: occipital bone and mastoid process
Action: pulls head back

Question 12

Semispinalis capitus

Answer 12

Origin: articular process of C4-C6
Insertion: between superior and inferior nuchal lines or occipital bones
Action: pulls head back

Question 13

External intercostals

Answer 13

Origin: inferior border of superior rib
Insertion: superior borders of inferior rib
Action: elevates ribs by causing them to moe up and out

Question 14

Internal intercostals

Answer 14

Origin: superior border of inferior rib
Insertion: inferior border of superior rib
Action: depresses the ribs during forced exhalation

Question 15

Diaphragm

Answer 15

Origin: inferior internal surface of lower ribs
Insertion: central tendon of
diaphragm
Action: contraction during inhalation

Question 16

External oblique

Answer 16

Origin: external inferior borders of lower ribs
Insertion: linea alba by a broad aponeurosis
Action: compress the abdominal wall

Question 17

Internal oblique

Answer 17

Origin: lumbar fascia, inguinal ligament and iliac crest
Insertion: linea alba, pubic crest
Action: compress abdominal wall

Question 18

Transversus abdominis

Answer 18

Origin: iliac crest, lumbar fascia, inugila ligament
Insertion: linea alba and pubic crest
Action: compress abdominal wall

Question 19

Rectus abdominis

Answer 19

Origin: superior surface of pubis
Insertion: xiphoid process of sternum
Action: Flexes vertebral column and compresses the abdominal wall