MOSBY anA HYGIE Flashcards
- Which paired muscle covers most of the lateral aspect
of the ramus of the mandible?
A. Temporalis
B. Masseter
C. Lateral pterygoid
D. Medial pterygoid
ANS: B
The masseter (B) muscle is located on the lateral
aspect of the ramus of the mandible. The temporalis
(A) muscle is a large, fan-shaped muscle attached
to the coronoid process of the mandible. The lateral
pterygoid (C) has two heads and lies superiorly to the
medial pterygoid. The medial pterygoid (D) inserts on
the medial surface of the mandibular ramus. All these
muscles are muscles of mastication.
- During periodontal surgery, a fenestration is exposed
on tooth #6. A fenestration is a defect of which type of
bone?
A. Compact
B. Cancellous
C. Interdental
D. Interradicular
ANS: A
A fenestration is an opening or window in the solid
plate of compact (A) cortical bone on the facial
surface over the root of a tooth. Cancellous (B) bone
is located between the alveolar bone proper and the
plates of cortical bone. The interdental septum (C)
is bone located between the roots of adjacent teeth.
Interradicular (D) bone is located between the roots of
the same tooth
- The fibrous connective tissue membrane covering the
outside of bone is called the
A. endosteum.
B. periosteum.
C. hyaline cartilage.
D. articular cartilage.
ANS: B
Periosteum (B) is the fibrous connective tissue
membrane covering the outside of bone except at the
articular surfaces. Endosteum (A) is the connective
tissue membrane lining the marrow cavity of the bone.
Hyaline cartilage (C) is a flexible and slightly elastic
cartilage found in joints, costal cartilages, the nasal
septum, the larynx, and the trachea. Articular cartilage
(D) is specialized, thin, smooth hyaline cartilage
found on the joint surfaces of bones, for example, in a
synovial joint.
- What is the purpose of the synovial membrane in a
synovial joint?
A. Secrete fluid into the joint cavity
B. Surround the joint like a fibrous sleeve
C. Innervate the muscles that move the joint
D. Convey a sense of position and movement
ANS: A
The synovial membrane secretes synovial fluid (A),
which lubricates the synovial joint. The capsular
ligament surrounds the joint like a fibrous sleeve (B).
The sensory nerve endings innervate the muscles
that move the joint (C). Proprioceptive nerve endings
convey a sense of position and movement (D).
- Which component of a nerve conducts impulses
toward the cell body?
A. Axon
B. Soma
C. Neuron
D. Dendrite
ANS: D
Dendrites (D) are branching cellular extensions of a
nerve that conduct impulses toward the cell. An axon
(A) is a cellular extension of a nerve that conducts
impulses away from the cell. The soma (B) is the body
of the cell containing the nucleus. A neuron (C) is the
basic functional unit of the nervous system.
- Which spinal vertebrae fuse together to form a
triangular mass?
A. Sacral
B. Lumbar
C. Cervical
D. Thoracic
ANS: A
The sacral (A) vertebrae of the spinal cord fuse
together to form a triangular mass, called the
sacrum. The lumbar (B) region comprises the five
large vertebrae located between the thoracic and
sacral regions. The cervical (C) region comprises
the seven vertebrae located between the base of the
neck and the thoracic region. The thoracic (D) region
comprises the 12 vertebrae between the cervical and
lumbar regions
- The ophthalmic nerve is the first division of the fifth
cranial nerve V, the trigeminal nerve. The maxillary
nerve is the second division of the trigeminal nerve.
A. Both statements are true.
B. Both statements are false.
C. The first statement is true, and the second statement
is false.
D. The first statement is false, and the second
statement is true.
ANS: A
Both statements are true (A). Cranial nerve V is the
trigeminal nerve, of which the ophthalmic nerve
is the first division (V1
) and the maxillary nerve
is the second division (V2
). The third division of
the trigeminal nerve (V3
) is the mandibular nerve.
Choices B, C, and D do not accurately reflect the
statements.
- Which injections technique would be used to achieve
anesthesia of teeth #15 and #16?
A. Nasopalatine block
B. Anterosuperior alveolar block
C. Middle superior alveolar block
D. Posterosuperior alveolar block
ANS: D
The posterosuperior alveolar block (D) anesthetizes
the mesiobuccal root of the first maxillary molar
and the second and third maxillary molars. The
nasopalatine block (A) anesthetizes the premaxillary
area of the palate and the anterior maxillary teeth.
The anterosuperior alveolar block (B) anesthetizes
the gingiva and the anterior maxillary teeth. The
middle superior alveolar block (C) anesthetizes
the premolars and the mesiobuccal root of the first
maxillary molar.
- All of the following are foramina in the sphenoid bone
EXCEPT the
A. incisive foramen.
B. superior orbital fissure.
C. foramen ovale.
D. foramen rotundum.
ANS: A
The incisive foramen (A) is an opening to the incisive
canal in the palatine process of the maxilla. The
superior orbital fissure (B), foramen ovale (C), and
foramen rotundum (D) are all located in the sphenoid
bone and are exit points for cranial nerve V
- The infraorbital foramen is located in which bone?
A. Frontal
B. Maxilla
C. Zygomatic
D. Sphenoid
ANS: B
The infraorbital foramen passes through the maxilla
(B), not the frontal (A), zygomatic (C), or sphenoid
(D) bones.
- Which muscle retracts the tongue?
A. Genioglossus
B. Hyloglossus
C. Styloglossus
D. Palatoglossus
ANS: C
When the styloglossus (C) muscle contracts, the tongue
retracts. In contrast, the hyloglossus (B) will depress
the tongue upon contraction, and the genioglossus (A)
will protrude the tongue and depress portions. The
palatoglossus (D) elevates the base of the tongue, and
depresses the soft palate
- Which plane of dissection divides the body into
anterior and posterior portions?
A. Frontal
B. Sagittal
C. Horizontal
D. Median
ANS: A
The frontal (A) plane divides the body into anterior
and posterior portions. The sagittal plane (B) divides
the body in an anteroposterior direction. The horizontal
plane (C) separates the body into superior and inferior
portions, and the median plane (D) divides the body
into equal right and left halves.
- Teeth #3 and #14 are
A. ipsilateral to each other.
B. contralateral to each other.
C. inferior to each other.
D. superficial to each other.
ANS: B
Teeth #3 and #14 are the first maxillary molars on the
opposite arches of the mouth, which means that they
are contralateral to each other (B). Ipsilateral (A)
would mean that they are on the same side. Inferior
(C) applies to a structure that is beneath or lower than
another structure, and superficial (D) applies to a
structure that is near the surface. These are not terms
used to describe the dentition.
- The following characteristics describe muscle tissue
EXCEPT one. Which one is the EXCEPTION?
A. Each muscle has two ends.
B. Muscle cells are called sarcomeres.
C. Muscles are categorized according to their role in
movement.
D. The muscle origin is attached to the least movable
part.
E. The muscle insertion is attached to the most
movable part
ANS: B
The correct choice is B. Muscle cells are called
myocytes, whereas sarcomeres are the unit of contraction of the myofibrils of the muscle cell.
Muscles have two ends (A) and are categorized
according to their role in movement (C). The origin of
each muscle is defined by its least movable attachment
(D). In addition, the insertion is attached to the most
movable part (E)
- Which lymph nodes drain both sides of the chin, the
lower lip, the floor of mouth, the apex of tongue, and
the mandibular incisors?
A. Facial
B. Submental
C. Submandibular
D. Retropharyngeal
ANS: B
The submental (B) lymph nodes drain both sides of
the chin, the lower lip, the floor of mouth, the apex
of tongue, and the mandibular incisors. The facial
lymph nodes (A) are superficial nodes located along
the length of the facial vein and are further categorized
into four subgroups that drain the areas they are named
for: malar, nasolabial, buccal, and mandibular. The
submandibular nodes (C) drain the cheeks, the upper
lip, the body of the tongue, the anterior hard palate,
and all teeth except the mandibular incisors and the
maxillary third molars. The retropharyngeal lymph
nodes (D) drain the pharynx, the palate, the paranasal
sinuses, and the nasal cavity.
- Which endocrine gland matures T-lymphocytes for the
immune system and undergoes involution (reduces in
size) after puberty?
A. Thyroid
B. Thymus
C. Pancreas
D. Parathyroid
ANS: B
T-lymphocytes are processed in the thymus (B), where
they attain their mature function. The thymus is large
in infancy and shrinks after puberty. The thyroid
gland (A) produces two main hormones—thyroxine
(T4
) and triiodothyronine (T3
)—that circulate through
the bloodstream and have many effects on body
metabolism, growth, and development. The islet
cells of the pancreas (C) create and release important
hormones directly into the bloodstream. Two of the
main pancreatic hormones are insulin, which acts to
lower blood sugar, and glucagon, which acts to raise
blood sugar. Maintaining proper blood sugar levels
is crucial to the functioning of key organs, including
the brain, liver, and kidneys. The pancreas also has
an exocrine function in producing enzymes that aid
digestion. The parathyroid glands (D) regulate calcium
levels by secreting parathyroid hormone and calcitonin
into the bloodstream
- The corrugator supercilii is a muscle of facial
expression in which region?
A. Eye
B. Nose
C. Mouth
D. Scalp
ANS: A
The corrugator supercilii is a muscle of facial
expression located just superior to the eye (A) and deep to the superior portion of the orbicularis oculi
muscle. The nose (B), mouth (C), and scalp (D) are not
moved by the corrugator supercilii muscle
- Which muscle elevates the mandible?
A. Risorius
B. Buccinator
C. Medial pterygoid
D. Lateral pterygoid
ANS: C
Upon contraction, the medial pterygoid (C) elevates
the mandible. The risorius (A) stretches the lips
by pulling each labial commissure laterally. The
buccinator (B) compresses the cheeks during chewing
by retracting the labial commissure. The lateral
pterygoid (D) depresses, protrudes, and deviates the
mandible laterally.
- Which muscle originates from the alveolar process of
the maxilla, the alveolar process of the mandible, and
the pterygomandibular raphe?
A. Masseter
B. Risorius
C. Buccinator
D. Sternocleidomastoid
ANS: C
The buccinator (C) muscle is a thin, quadrilateral muscle
originating from the three areas listed above. The masseter
(A) originates from the zygomatic arch; the risorius (B)
originates from a fascia superficial to the masseter muscle;
and the sternocleidomastoid (D) originates from the
clavicle.
- Which part of the brain regulates homeostasis?
A. Medulla
B. Thalamus
C. Cerebellum
D. Hypothalamus
ANS: D
The hypothalamus (D) regulates homeostasis in
the body. The medulla (A) is part of the brain stem
and is involved in regulating the components of
the autonomic nervous system. The thalamus (B)
plays a major role in relaying nerve impulses. The
cerebellum (C) is responsible for the coordination of
voluntary movements and for maintaining posture
and balance.
- Which branch of the trigeminal nerve contains both
sensory and motor components?
A. Ophthalmic V1
B. Maxillary V2
C. Mandibular V3
ANS: C
The mandibular or third division of the fifth cranial
nerve V3
(C), or the trigeminal nerve, has both afferent
or sensory and efferent or motor components. The
afferent component provides sensation to the teeth
and tissues of the mandible and the anterior two thirds
of the tongue. The efferent component innervates the
muscles of mastication, tensor tympani, and tensor veli
palatini. The ophthalmic V1
(A), or the first division
of the trigeminal nerve, provides sensation to the
conjunctivae, cornea, eyeball, orbit, forehead, ethmoid
and frontal sinuses, and part of the dura mater. The
second branch of the trigeminal nerve, maxillary V2
(B), carries sensory information for the maxillae and overlying skin, maxillary sinuses, nasal cavity, palate,
nasopharynx, and part of the dura mater.
- Which of the following are the two main divisions or
systems of the autonomic nervous system?
A. Brain, spinal cord
B. Afferent impulse, efferent impulse
C. Sympathetic system, parasympathetic system
ANS: C
Sympathetic and parasympathetic (C) systems are the
two divisions of the autonomic nervous system. The
brain and the spinal cord (A) are structures within the
central nervous system. Afferent impulse is the sensory
nerve impulse traveling toward the central nervous
system, and efferent impulse is the motor nerve impulse
traveling to the muscles that will move in response (B).
- Which cranial nerve provides parasympathetic innervation
to the cardiac muscles, thymus, and stomach?
A. IV
B. X
C. XI
D. XII
ANS: B
Cranial nerve X (B), the vagus nerve, sends
parasympathetic fibers to many organs, including the
thymus and the muscles of the heart and stomach.
Cranial nerve IV (A), the trochlear nerve, serves as an
efferent nerve for a muscle of the eye. Cranial nerve
XI (C), the accessory nerve, serves as an efferent nerve
for various muscles of the head and neck. Cranial
nerve XII (D), the hypoglossal nerve, innervates
intrinsic and extrinsic muscles of the tongue.
- Which of the following is NOT innervated by the
middle superior alveolar nerve?
A. Tooth #4
B. Tooth #12
C. Distobuccal root of tooth #2
D. Mesiobuccal root of tooth #14
ANS: C
The distobuccal root of the maxillary second molar,
tooth #2 (C), is innervated by the posterosuperior
alveolar nerve, not the middle superior alveolar
nerve. The middle superior alveolar nerve innervates
maxillary premolars, teeth #4 and #5 (A) and, #12 and
#13 (B), and the mesiobuccal root of maxillary first
molars, teeth #3 and #14 (D).
- The muscles of facial expression are innervated by
which nerve?
A. IV
B. V
C. VII
D. VIII
ANS: C
Cranial nerve VII (C), the facial nerve, innervates the
muscles of facial expression. Cranial nerve IV (A),
the trochlear nerve, serves as an efferent nerve for a
muscle of the eye. Cranial nerve V (B), the trigeminal
nerve, serves as an afferent nerve to the oral cavity,
teeth, and most of the skin of the face and head, as well
as efferent innervations for the muscles of mastication
and some of the muscles of the palate. Cranial nerve
VIII (D), the vestibulocochlear nerve, is an afferent
nerve for hearing and balance
- Which vein receives blood flow from the superficial
temporal vein and the facial vein and drains into the
external jugular vein?
A. Maxillary
B. Ophthalmic
C. Inferior alveolar
D. Retromandibular
ANS: D
The retromandibular (D) vein receives blood flow
from the superficial temporal vein and the facial vein
and drains into the external jugular vein. It is situated
immediately posterior to the angle of the mandible. The
maxillary vein (A) receives blood flow from the pterygoid
plexus and drains into the retromandibular vein. The
ophthalmic vein (B) drains the tissue of the orbit and
proceeds into the facial vein. The inferior alveolar vein
(C) forms from the merging of the dental, alveolar, and
mental branches and drains into the pterygoid plexus
- The articulation of the temporomandibular joint
involves which two bones?
A. Temporal bone, mental protuberance
B. Sphenoid bone, coronoid process of the mandible
C. Temporal bone, mandibular condyles
ANS: C
Temporal bone and mandibular condyle (C) articulate
to form part of the temporomandibular joint. Neither
temporal bone and mental protuberance (A) nor
sphenoid bone and the coronoid process of the
mandible (B) articulate with each other
- Which artery supplies the mandibular teeth and
surrounding tissues with blood?
A. Facial
B. Lingual
C. Inferior alveolar
D. Pterygoid plexus
ANS: C
The inferior alveolar artery (C) is a branch of the
maxillary artery and supplies the mandibular teeth, the
floor of the mouth, and the mental region with blood.
The facial artery (A) is also known as the external
maxillary artery and extends to the mid-face region to
supply the oral, buccal, zygomatic, nasal, infraorbital,
and orbital regions. The lingual artery (B) is an anterior
branch from the external carotid artery and supplies the
tissue superior to hyoid bone, including the suprahyoid
muscles and the floor of the mouth. The pterygoid plexus
(D) supplies the deep facial areas and the posterosuperior
alveolar vein and the inferior alveolar vein.
- Which major artery supplies the brain with blood and
is palpated during emergency situations?
A. Aorta
B. Subclavian
C. Internal carotid
D. Common carotid
ANS: D
The common carotid artery (D) runs superiorly along
the neck, lateral to the trachea and the larynx. When
palpated against the larynx, the most reliable arterial
pulse of the body can be monitored. The aorta (A) is a
major artery, which gives rise to the common carotid
artery and the subclavian artery (B) on the left side
of the heart and the brachiocephalic artery on the
right side of the heart. The internal carotid artery (C)
supplies the anterior part of the brain and the eye and sends branches to the forehead and the nose. The aorta
(A), the subclavian artery (B), and the internal carotid
artery (C) cannot be reliably palpated in an emergency.
- Which artery is the source of the ophthalmic
artery, has NO branches, and is located deep to the
sternocleidomastoid muscle?
A. Aorta
B. Subclavian
C. External carotid
D. Internal carotid
ANS: D
The internal carotid artery (D) is a branchless division
of the common carotid artery, which is covered by the
sternocleidomastoid muscle, and supplies blood to the
ophthalmic artery. The aorta (A), a major artery that is a
portion of the heart itself gives rise to the common carotid
artery and the subclavian artery (B) on the left side of the
heart and the brachiocephalic artery on the right side of
the heart. The external carotid artery (C) travels superiorly
to the internal carotid artery and has four sets of branches.
- The facial artery is a direct branch of which main
artery?
A. Subclavian
B. Internal carotid
C. External carotid
D. Brachiocephalic
ANS: C
The facial artery is the final anterior branch from
the external carotid artery (C), not the subclavian
artery (A), the internal carotid artery (B), or the
brachiocephalic artery (D).
- The facial vein drains each region of the head and neck
EXCEPT one. Which one is the EXCEPTION?
A. Orbital region
B. Upper lip area
C. Lower lip area
D. Submental region
ANS: A
The orbital region (A) is drained by the cavernous
sinus and the pterygoid plexus, not the facial vein. The
facial vein drains the upper lip (B), the lower lip (C),
and the submental region (D).
- Which of the following arteries supplies maxillary
anterior teeth with blood?
A. Incisive
B. Mylohyoid
C. Greater palatine
D. Anterior superior alveolar
ANS: D
Maxillary anterior teeth are supplied by the
anterosuperior alveolar artery (D). The incisive artery
(A) supplies the periodontium of the mandibular
anterior teeth, including the associated gingiva. The
mylohyoid artery (B) supplies the floor of the mouth
and the mylohyoid muscle. The greater palatine artery
(C) supplies the hard and soft palates.
- Veins of teeth have alveolar branches and dental
branches. Which branch type would drain the pulp
tissue of teeth through the apical foramen?
A. Alveolar branches
B. Dental branches
C. Both A and B
D. Neither A nor B
ANS: B
The incisive artery branches off the inferior alveolar
artery, remaining within the mandibular canal to divide into dental and alveolar branches. The dental branches
(B) of the pulp drain the mandibular anterior teeth
by way of each tooth’s apical foramen. The alveolar
branches (A) of the periodontium drain the mandibular
anterior teeth, including the gingiva. Choices C and D
do not correctly address the statement.
- Which vein has NO valves, drains most of the head
and neck region, and does NOT drain any of the
dentition?
A. Internal jugular
B. External jugular
C. Internal maxillary
D. Inferior alveolar
ANS: A
The internal jugular vein (A) drains most of the head
and the neck, except the dentition. The external jugular
vein (B) is the only vein the head and neck with valves.
The internal maxillary vein (C) drains the pterygoid
plexus, whereas the inferior alveolar vein (D) drains
the mandibular teeth and the periodontium
- Many veins in the head and neck region lack valves.
Valveless veins of the head and neck contribute to the
severe and rapid spread of dental infections.
A. Both statements are true.
B. Both statements are false.
C. The first statement is true, and the second statement
is false.
D. The first statement is false, and the second
statement is true.
ANS: A
The correct choice is A; both statements are true.
Most veins in the head and neck lack valves, with the
exception of the external jugular vein. The lack of
valves in the veins of the head and neck may contribute
to severe and rapid spread of dental infections. Choi
- Each of the following is an afferent cranial nerve
EXCEPT one. Which one is the EXCEPTION?
A. Optic
B. Vagus
C. Olfactory
D. Hypoglossal
ANS: D
The hypoglossal nerve (D) is an efferent (motor) cranial
nerve for both intrinsic and extrinsic muscles of the
tongue. The optic nerve (A), the vagus nerve (B), and
the olfactory nerve (C) are afferent, or sensory, nerves.
- Which muscle, upon contraction, protrudes the tongue?
A. Genioglossus
B. Hyloglossus
C. Styloglossus
ANS: A
The genioglossus muscle (A) protrudes the tongue
upon contraction. The hyloglossus muscle (B)
depresses the tongue when it contracts. Upon
contraction, the styloglossus muscle (C) retracts the
tongue.
- Each of the following is a suprahyoid muscle EXCEPT
one. Which one is the EXCEPTION?
A. Mylohyoid
B. Geniohyoid
C. Stylohyoid
D. Sternohyoid
ANS: D
The sternohyoid muscle (D) is an infrahyoid muscle.
The mylohyoid (A), geniohyoid muscle (B), and
stylohyoid (C) muscles are all suprahyoid muscles.