Exam 3: Chapter 11, Axial Muscles

Digastric (two bellies)

a Suprahyoid muscle depresses mandible, elevates hyoid

hyoglossus muscles (left/right)

insert on sides of tongue depress and retract tongue originate on hyoid bone

buccinator

prevents "chipmunk cheeks"

• Omohyoid • Sternohyoid • Thyrohyoid • Sternothyroid pulls down (Depresses) cartilage and hyoid bone

Infrahyoid muscles names and function

• Stylohyoid muscle • Geniohyoid muscle • Mylohyoid

Suprahyoid muscles above hyoid bone

palatoglossus muscles (left/right)

elevate posterior portion of tongue originate on soft palate

temporalis extends from temporal lines on parietal and frontal bones to coronoid process of mandible (deep to zygomatic process)

elevates and retracts mandible

sternocleidomastoid

Contraction of both flexes the neck Contraction of one rotates head to opposite side and laterally flexes neck

Facial Expression Muscles 1. levator labii superioris • extends from under eye to upper lip, pulls upper lip up in snarl or sneer 2. 3. zygomaticus major and zygomaticus minor • zygomaticus major and zygomaticus minor pull corner of mouth superiorly and laterally, smile 4. risorius • pulls corner of mouth laterally, smile

Facial Expression Muscles 1. pulls upper lip up in snarl or sneer 2. 3. pull corner of mouth superiorly and laterally, smile 4. pulls corner of mouth laterally, smile

Superior rectus

Look at ceiling attaches to anterosuperior surface of eye pulls eye up and medially (look at procerus muscle)

Medial rectus

attaches to anteromedial surface of eye pulls eye medially (toward bridge of nose)

Facial Expression Muscles 1. depressor anguli oris "frown" muscle pulls corners of mouth down 2. depressor labii inferioris pulls lower lip down 3. Orbicularis oris surrounds mouth closes mouth, puckers lips

1. "frown" muscle pulls corners of mouth down 2. pulls lower lip down 3. surrounds mouth closes mouth, puckers lips

1. mentalis • attaches to lower lip, protrudes lower lip (pout) 2. platysma • tenses skin of neck, pulls lower lip down 3. buccinator compresses cheek against teeth protrudes lower lip (pout) 4. masseter raises and lowers jaw

1. attaches to lower lip, protrudes lower lip (pout) 2. tenses skin of neck, pulls lower lip down 3. compresses cheek against teeth protrudes lower lip (pout) 4. raises and lowers jaw

Facial Expression Muscles 1. Corrugator supercilii • draws eyebrows together • creates vertical wrinkles above nose 2. nasalis "flares the nostrils" 3. procerus wrinkles the nose

1. draws eyebrows together • creates vertical wrinkles above nose 2. "flares the nostrils" 3. wrinkles the nose

Genioglossus - originate on mandible

all along the bottom of the tongue. tongue depressor, choke • protract tongue • Miley muscle

inferior oblique

inserts on posterior inferior part of eye pulls back of eye down (eye looks up)

styloglossus

originate on styloid process of temporal bone elevate and retract tongue

medial and lateral pterygoid originate on pterygoid plate of sphenoid bone, insert on mandible

protract mandible move mandible side to side

Superior oblique

pulls eye down hooks through trochlea inserts on posterior superior part of eye pulls back of eye up (eye looks down)

Oblique eye muscles

pulls on an angle originate from within the orbit inserts on posterolateral part of eye

Facial Expression Muscles 1. Levator palpebrae superioris raises eyelid opens the eye 2. orbicularis oculi surrounds orbit of eye. closes eye (wink, blink, squint)

1. raises eyelid opens the eye 2. closes eye (wink, blink, squint)

scalene (there are 3)

Originate from transverse processes of C2 to C7 Insert onto ribs 1 and 2 Elevate ribs 1 and 2 during inhalation

Lateral rectus

attaches to anterolateral surface of eye pulls eye laterally (toward ear) (goes straight)

Erector spinae

group of muscles that maintain posture

Extrinsic muscles

have origin on other head and neck structures, insert on tongue end in -glossus

Masseter

connects zygomatic process to mandible elevates and protracts mandible most powerful chewing muscle

pharyngeal constrictor muscles

contract sequentially to swallow food

Intrinsic muscles

curl, squeeze and fold tongue sit inside tongue tongue acts like muscle, but actually isn't

Inferior rectus

(look at floor) attaches to anteroinferior surface of eye pulls eye down and medially (look at tip of nose)