PCSD 313 Module IV Articulation and Resonance Questions with
Correct Answers (Grade A+)
Question 1: 1. Muscles of the Tongue 2. Muscles of the Velopharyngeal Mechanism 3. Muscles of
Mastication 4. Muscles of Facial Expression
Answer: There are 4 groups of articulatory muscles:
Question 2: OO is the primary muscle of the lips. It is an oval ring of muscles located within the lips.
It completely encircles the oral opening. It is comprised of short fibers that overlap in a circular
fashion.
Answer: Orbicularis Oris [OO]
Question 3: 1. Orbicularis Oris 2. Transverse Muscles A. Buccinator (2) B. Risorius (2) 3. Angular
Muscles: A. Zygomatic Major (2) B. Levator Labii Superior (2) 4. Vertical Muscles: A. Levator
Anguli Oris (2) B. Depressor Anguli Oris (2) C. Mentalis 5. Other: Frontalis (2) Orbicularis Oculi (2)
Nasalis (2) Platysma (1)
Answer: Muscles of Facial Expression
Question 4: It is a sphincter muscle. Function - A. When active, it closes the mouth & puckers the
lips. B. When activated with other muscles, it will close the mouth in a straight line.
Answer: OO
Question 5: Buccinator is the primary muscle of the cheek. It is the deepest of the facial muscles. It
originates on the pterygomandibular ligament (hamulus to the last molar). It courses horizontally &
anteriorly. Its fibers decussate [cross] at the corners of the oral cavity to insert into OO. Function:
Draws the corners of the mouth laterally.
Page 1
, Answer: Transverse Muscle: Buccinator
Question 6: Origin: Fascia covering masseter Course: Horizontally & anteriorly. Parallel &
superficial to buccinator. Insert: Skin & mucosa at corners of oral cavity [OO] Function: Assists in
drawing corners of mouth laterally.
Answer: Transverse Muscle: Risorius
Question 7: Origin: Surface of Zygomatic bone Course: Inferiorly & medially Insert: OO and skin at
corner of oral cavity. Function: Draws corners of mouth superiorly & laterally to form a broad
smile.
Answer: Angular Muscle: Zygomatic Major
Question 8: Origin: Lower margin of the orbit of the eye. Course: Inferiorly Insert: Upper lip, lateral
to levator anguli oris Function: Elevates the upper lip.
Page 2
, Answer: Angular Muscle: Levator Labii Superior
Question 9: Origin: Mandible, just lateral to midline Course: Superiorly and medially Insert: Lower
lip Function: Draws lower lip inferiorly and laterally.
Answer: Angular Muscle: Depressor Labii Inferior
Question 10: Origin: lateral to the nasal ala Course: Inferiorly Insert: Into OO with some fibers
decussating to the lower lip Function: Draws corners of the oral cavity superiorly & aids in closing
the lower lip.
Answer: Vertical Muscle: Levator Anguli Oris
Question 11: Origin: Mandible, slightly lateral to midline Course: Superior Insertion: OO with some
fibers crossing to upper lip Function: Depresses the angle of the lip and draw the upper lip down
Answer: Vertical: Depressor Anguli Oris
Question 12: Origin: Mental tuberosity of the mandible Course: Superior Insertion: Some fibers
insert into the chin, some into OO Function: Contraction will evert the lower lip, wrinkle the chin,
and stiffen the lower lip so that the mouth can be closed in a line
Page 3
Correct Answers (Grade A+)
Question 1: 1. Muscles of the Tongue 2. Muscles of the Velopharyngeal Mechanism 3. Muscles of
Mastication 4. Muscles of Facial Expression
Answer: There are 4 groups of articulatory muscles:
Question 2: OO is the primary muscle of the lips. It is an oval ring of muscles located within the lips.
It completely encircles the oral opening. It is comprised of short fibers that overlap in a circular
fashion.
Answer: Orbicularis Oris [OO]
Question 3: 1. Orbicularis Oris 2. Transverse Muscles A. Buccinator (2) B. Risorius (2) 3. Angular
Muscles: A. Zygomatic Major (2) B. Levator Labii Superior (2) 4. Vertical Muscles: A. Levator
Anguli Oris (2) B. Depressor Anguli Oris (2) C. Mentalis 5. Other: Frontalis (2) Orbicularis Oculi (2)
Nasalis (2) Platysma (1)
Answer: Muscles of Facial Expression
Question 4: It is a sphincter muscle. Function - A. When active, it closes the mouth & puckers the
lips. B. When activated with other muscles, it will close the mouth in a straight line.
Answer: OO
Question 5: Buccinator is the primary muscle of the cheek. It is the deepest of the facial muscles. It
originates on the pterygomandibular ligament (hamulus to the last molar). It courses horizontally &
anteriorly. Its fibers decussate [cross] at the corners of the oral cavity to insert into OO. Function:
Draws the corners of the mouth laterally.
Page 1
, Answer: Transverse Muscle: Buccinator
Question 6: Origin: Fascia covering masseter Course: Horizontally & anteriorly. Parallel &
superficial to buccinator. Insert: Skin & mucosa at corners of oral cavity [OO] Function: Assists in
drawing corners of mouth laterally.
Answer: Transverse Muscle: Risorius
Question 7: Origin: Surface of Zygomatic bone Course: Inferiorly & medially Insert: OO and skin at
corner of oral cavity. Function: Draws corners of mouth superiorly & laterally to form a broad
smile.
Answer: Angular Muscle: Zygomatic Major
Question 8: Origin: Lower margin of the orbit of the eye. Course: Inferiorly Insert: Upper lip, lateral
to levator anguli oris Function: Elevates the upper lip.
Page 2
, Answer: Angular Muscle: Levator Labii Superior
Question 9: Origin: Mandible, just lateral to midline Course: Superiorly and medially Insert: Lower
lip Function: Draws lower lip inferiorly and laterally.
Answer: Angular Muscle: Depressor Labii Inferior
Question 10: Origin: lateral to the nasal ala Course: Inferiorly Insert: Into OO with some fibers
decussating to the lower lip Function: Draws corners of the oral cavity superiorly & aids in closing
the lower lip.
Answer: Vertical Muscle: Levator Anguli Oris
Question 11: Origin: Mandible, slightly lateral to midline Course: Superior Insertion: OO with some
fibers crossing to upper lip Function: Depresses the angle of the lip and draw the upper lip down
Answer: Vertical: Depressor Anguli Oris
Question 12: Origin: Mental tuberosity of the mandible Course: Superior Insertion: Some fibers
insert into the chin, some into OO Function: Contraction will evert the lower lip, wrinkle the chin,
and stiffen the lower lip so that the mouth can be closed in a line
Page 3
