u u u u u u u
dern Dental Assisting 14th Edition
u u u u
Editorsu:
JeffreyuR.uSmithu&uDebbieuS.uRobinson
,Chapteru1.uOraluEmbryologyuanduHistology
1. Whichuofutheufollowinguisutheuprocessubyuwhichutheucellsuofutheufertilizedueggudivideuanduf
ormuauballuofucellsuduringuembryonicudevelopment?
A. Cleavage
B. Differentiation
C. Organogenesis
D. Implantation
Answer:uA.uCleavage
Rationale:uCleavageuisutheuseriesuofurapidumitoticudivisionsuthatuoccuruafterufertilization,ul
eadingutoutheuformationuofuauballuofucellsuknownuasutheumorula.
DIF:uEasy
TOP:uEmbryonicudevelopmentu
MSC:uMultipleuChoice
2. Duringutheufirstuweekuofuembryonicudevelopment,utheufertilizedueggubecomesuaustructureuc
alledua:
A. Zygote
B. Blastocyst
C. Morula
D. Embryo
Answer:uB.uBlastocyst
Rationale:uAfterufertilizationuanducleavage,utheuballuofucellsu(morula)uformsuintouaub
lastocyst,uwhichuimplantsuintoutheuuterineuwall.
DIF:uEasy
TOP:uEmbryonicudevelopmentu
MSC:uMultipleuChoice
3. Theuoralucavityubeginsutoudevelopuduringuwhichuofutheufollowingustagesuofuembryonicud
evelopment?
A. Zygote
B. Fetal
C. Pre-implantation
D. Embryonic
Answer:uD.uEmbryonic
Rationale:uTheudevelopmentuofutheuoralucavityustartsuduringutheuembryonicustage,uaroundut
heuthirduweekuofupregnancy,uasutheufacialustructuresubeginutouform.
DIF:uModerate
TOP:uOralucavityudevelopmentu
MSC:uMultipleuChoice
4. Theuprocessubyuwhichutheuneuralutubeuformsuandubeginsutoudevelopuintoutheubrainuandus
pinalucorduisuknownuas:
A. Gastrulation
B. Neurulation
C. Cleavage
D. Organogenesis
, Answer:uB.uNeurulation
Rationale:uNeurulationuisutheuprocessuwhereutheuneuralutubeuforms,uwhichulaterugivesuriseut
outheucentralunervoususystemu(brainuanduspinalucord).
DIF:uModerate
TOP:uNeuraludevelopmentu
MSC:uMultipleuChoice
5. Whichuofutheufollowinguisutheuprimaryufunctionuofutheumesodermulayeruinuembryonicud
evelopment?
A. Formationuofutheunervoususystem
B. Developmentuofutheuskinuanduhair
C. Formationuofumuscles,ubones,uanducirculatoryusystems
D. Formationuofutheudigestiveusystem
Answer:uC.uFormationuofumuscles,ubones,uanducirculatoryusystems
Rationale:uTheumesodermulayerugivesuriseutoustructuresusuchuasumuscles,ubones,uandutheuc
irculatoryusystemuduringuembryonicudevelopment.
DIF:uModerateuT
OP:uGermulayers
MSC:uMultipleuChoice
6. Theutermu"histology"urefersutoutheustudyuof:
A. Theustructureuandufunctionuofutissues
B. Theudevelopmentuofuorgans
C. Theustructureuofucells
D. Theudevelopmentuofuembryos
Answer:uA.uTheustructureuandufunctionuofutissues
Rationale:uHistologyuisutheustudyuofutissues,uincludingutheirustructureuandufunction,uandut
heiruroleuinutheubody.
DIF:u EasyuTOP
:uHistology
MSC:uMultipleuChoice
7. Theuenameluofutheutoothuisuderivedufromuwhichuembryonicutissue?
A. Ectoderm
B. Mesoderm
C. Endoderm
D. Neuralucrest
Answer:uA.uEctoderm
Rationale:uEnamel,utheuharduouterusurfaceuofutheutooth,udevelopsufromutheuectodermalul
ayeruofutheuembryo.
DIF:uModerate
TOP:uToothudevelopmentu
MSC:uMultipleuChoice
8. Theudevelopmentuofutheufaceuanduoralucavityuduringuembryonicudevelopmentuinvolvesuf
usionuofuwhichustructures?
A. Palatalushelves
B. Maxillaryuandumandibularuprocesses
C. Frontalunasaluprocess
D. BothuBuanduC
, Answer:uD.uBothuBuanduC
Rationale:uTheudevelopmentuofutheufaceuanduoralucavityuinvolvesutheufusionuofutheu
maxillaryuandumandibularuprocesses,uasuwelluasutheufrontalunasaluprocess.
DIF:uModerate
TOP:uFacialudevelopmentu
MSC:uMultipleuChoice
9. Whichustructureuisuresponsibleuforutheuformationuofutheuteethuduringuembryonicud
evelopment?
A. Neuralucrest
B. Ectoderm
C. Mesoderm
D. Endoderm
Answer:uA.uNeuralucrest
Rationale:uTheuneuralucrestucellsuplayuaucrucialuroleuinutheuformationuofutheuteethuduringue
mbryonicudevelopment.
DIF:uModerate
TOP:uToothuformationu
MSC:uMultipleuChoice
10. Theufirstuindicationuofutoothudevelopmentuoccursuduringuwhichuweekuofuembryonicud
evelopment?
A. 2nduweek
B. 5thuweek
C. 6thuweek
D. 7thuweek
Answer:uC.u6thuweek
Rationale:uTheufirstuindicationuofutoothudevelopmentuappearsuduringutheu6thuweekuofue
mbryonicudevelopment,uwhenutheudentalulaminauforms.
DIF:uModerate
TOP:uToothudevelopmentu
MSC:uMultipleuChoice
11. Theuprocessuofuossificationurefersuto:
A. Theuformationuofublooducells
B. Theuformationuofubone
C. Theudevelopmentuofutheuskin
D. Theudevelopmentuofutheudigestiveusystem
Answer:uB.uTheuformationuofubone
Rationale:uOssificationuisutheuprocessubyuwhichuboneutissueuisuformedufromucartilageuoruo
theruconnectiveutissue.
DIF:uModerate
TOP:uBoneudevelopmentu
MSC:uMultipleuChoice
12. Whichuofutheufollowinguisuaukeyufeatureuofutheuhistologicalustructureuofuenamel?
A. Ituisucomposeduofucollagenufibers
B. Ituisuavascularuanduhasunoulivingucells
C. Itucontainsumanyublooduvessels
D. Ituhasuauhighucontentuofuwater