Superficial Face/Muscles of Mastication, Larynx and Pharynx

Question 1

Buccinator

Answer 1

Cheek Muscle

Innervation:
Facial Nerve (CN VII) via Buccal Branches

Action:
Presses cheek against molar teeth; works with tongue to keep food between occlusal surfaces and out of oral vestibule; resists distention (when blowing)

Question 2

Occipitofrontalis (Frontal Belly)

Answer 2

Innervation:
Facial Nerve (CN VII) via Temporal branch

Action:
Elevates eyebrows and wrinkles skin of forehead; protracts scalp (indicating surprise or curiosity)

Question 3

Orbicularis Oculi (Orbital Sphincter)

Answer 3

Innervation:
Facial Nerve (CN VII) via Temporal Branch

Action:
Closes eyelids: palpebral part does so gently; orbital part tightly (winking)

Question 4

Orbicularis Oris (Oral Sphincter)

Answer 4

Innervation:
Facial Nerve (CN VII) via Buccal Branch

Action:
Tonus closes mouth; phasic contraction compresses and protrudes lips (kissing) or resists distention (when blowing)

Question 5

Masseter

Answer 5

Muscle of Mastication

Origin:
Quadrate muscle attaching to inferior border and medial surface of maxillary process of zygomatic bone and the zygomatic arch

Insertion:
Angle and lateral surface of ramus of mandible

Innervation:
Anterior trunk of mandibular nerve (CN V3); Via Masseteric Nerve

Action:
Elevates mandible; superficial fibers make limited contribution to protrusion of mandible

Question 6

Temporalis

Answer 6

Muscle of Mastication

Origin:
Triangular muscle with broad attachment to floor of temporal fossa and deep surface of temporalis fascia

Insertion:
Narrow attachment to tip and medial surface of coronoid process and anterior border of ramus of mandible

Innervation:
Anterior trunk of mandibular nerve (CN V3); Via Deep Temporal Nerves

Action:
Elevates mandible, closing jaws; posterior, more horizontal fibers are retractors of mandible

Question 7

Occipitofrontalis (Occipital belly)

Answer 7

Innervation:
Facial Nerve (CN VII) via Posterior auricular branch

Action:
Retracts scalp; increasing effectiveness of frontal belly

Question 8

Facial Nerve (CN VII)

Answer 8

Branches:
temporal, zygomatic, buccal, marginal
mandibular, cervical.

Question 9

Trigeminal Nerve (CN V)

Answer 9

Function:
The Sensory nerve for Face
The Motor nerve for muscles of mastication.

Branches:
supraorbital,
infraorbital, mental (branches of V1, V2,
and V3 respectively)

Question 10

Platysma

Answer 10

Innervation:
Facial Nerve (CN VII) via Cervical Branch

Action:
Depresses mandible (against resistance); tenses skin of inferior face and neck (conveying tension and stress)

Question 11

Lateral Pterygoid

Answer 11

Origin:
Triangular 2-headed muscle from (1) Infratemporal surface and crest of greater wing of sphenoid and (2) Lateral surface of lateral pterygoid plate

Insertion:
Superior head attaches primarily to joint capsule and articular disc of TMJ; Inferior head attaches primarily to pterygoid fovea on anteromedial aspect of neck of condyloid process of mandible

Innervation:
Anterior trunk of mandibular nerve (CN V3) via nerves to lateral pterygoid

Action:
Acting bilaterally, protracts mandible and depresses chin; acting unilaterally, swings jaw toward contralateral side; alternate unilateral contraction produces larger lateral chewing movements

Question 12

Medial Pterygoid

Answer 12

Origin:
Quadrangular 2-headed muscle from (1) medial surface of lateral pterygoid plate and pyramidal process of palatine bone and (2) tuberosity of maxilla

Insertion:
Medial surface of ramus of mandible, inferior to mandibular foramen; in essence, a “mirror image” of the ipsilateral masseter, the 2 muscles flanking the ramus

Innervation:
Anterior trunk of mandibular nerve (CN V3) via nerve to medial pterygoid.

Action:
Acts synergistically with masseter to elevate mandible; contributes to protrusion; alternate unilateral activity produces smaller grinding movements

Question 13

Superior Pharyngeal Constrictor

Answer 13

External Layer of Pharynx

Innervation:
Pharyngeal branch of Vagus (CN X) and pharyngeal plexus.

Action:
Constrict walls of Pharynx during swallowing

Question 14

Middle and Inferior Pharyngeal Constrictors

Answer 14

External Layer of Pharynx

Innervation:
Pharyngeal branch of Vagus (CN X) and pharyngeal plexus, plus branches of external and recurrent laryngeal nerves of vagus.

Action:
Constrict walls of Pharynx during swallowing

Question 15

Stylopharyngeus

Answer 15

Internal Layer of Pharynx muscles

Innervation:
Glossopharyngeal nerve (CN IX)

Action:
Elevate (shorten and widen) pharynx and larynx during swallowing and speaking

Question 16

Nasopharynx

Answer 16

Posterior to the nose and superior to the soft palate

Has respiratory function

Question 17

Oropharynx

Answer 17

Posterior to the mouth

Has disgestive function

Question 18

Laryngopharynx

Answer 18

Posterior to the larynx

Runs from C4-C6.

Question 19

Epiglottis

Answer 19

Heart shaped cartilage covered with mucous membrane. Situated posterior to the root of the tongue and the hyoid anterior to the laryngeal inlet.

Question 20

Larynx

Answer 20

Function:
Voice Production

Location:
C3-C6 vertebrae
Connects pharynx with trachea

Question 21

Thyroid Cartilage

Answer 21

The largest of the cartilages.

Superior border lies opposite to the C4 Vertebrae.

Question 22

Cricoid Cartilage

Answer 22

Forms a complete ring around the airway, the only cartilage of the respiratory tract to do so.

Smaller but thicker and stronger than thyroid cartilage

Lies at C6

Question 23

Arytenoid Cartilage

Answer 23

Paired, three-sided pyramidal cartilages that articulate with lateral parts of the superior border of the cricoid cartilage lamina.

Question 24

Laryngeal Vestibule

Answer 24

Between the laryngeal inlet and vestibular folds

Question 25

Laryngeal Ventricle

Answer 25

Recesses extending laterally from the middle part of the laryngeal cavity between vestibular and vocal folds.

Question 26

Vocal Folds (true vocal cords)

Answer 26

Control sound production.

The source of sounds (tone) that come from the larynx.

Question 27

Glottis

Answer 27

Vocal apparatus of the larynx. makes up vocal folds and processes, together with the rima glottidis.

Question 28

Vestibular folds

Answer 28

False vocal cords.
Have little to no role in voice production.
Function is to Protect.

Extending between the posterior aspect of the laryngeal prominence and arytenoid cartilages.

Question 29

Cricothyroid Muscle

Answer 29

Innervation:
External Laryngeal nerve from CN X

Action:
Stretches and tenses vocal ligament.

Question 30

Posterior Cricoarytenoid Muscle

Answer 30

Innervation:
Inferior laryngeal nerve (terminal part of recurrent laryngeal nerve, from CN X)

Action:
Abducts Vocal Cords

Question 31

Internal Laryngeal Nerve

Answer 31

The larger terminal branch of the superior laryngeal nerve. Pierces thyroid membrane with superior laryngeal artery,

supplying fibers to the laryngeal mucous membrane of the laryngeal vestibule and middle laryngeal cavity including superior surface of vocal folds.

Question 32

External Laryngeal Nerve

Answer 32

Descends posterior to the sternothyroid muscle in company with the superior thyroid artery

Supplies cricothyroid muscle

Question 33

Inferior laryngeal nerve

Answer 33

A continuation of the recurrent laryngeal nerve (a branch of the vagus nerve)

Supplies all intrinsic muscles of the larynx except the cricothyroid, which is supplied by the external laryngeal nerve.