c c c c c
Modern Dental Assisting 14th Edition
c c c c
Editorsc:
JeffreycR.cSmithc&cDebbiecS.cRobinson
,Chapterc1.cOralcEmbryologycandcHistology
1. Whichcofcthecfollowingciscthecprocesscbycwhichctheccellscofcthecfertilizedceggcdividecandcfo
rmcacballcofccellscduringcembryoniccdevelopment?
A. Cleavage
B. Differentiation
C. Organogenesis
D. Implantation
Answer:cA.cCleavage
Rationale:cCleavageciscthecseriescofcrapidcmitoticcdivisionscthatcoccurcaftercfertilization,clea
dingctocthecformationcofcacballcofccellscknowncascthecmorula.
DIF:cEasy
TOP:cEmbryoniccdevelopmentc
MSC:cMultiplecChoice
2. Duringcthecfirstcweekcofcembryoniccdevelopment,cthecfertilizedceggcbecomescacstructurecc
alledca:
A. Zygote
B. Blastocyst
C. Morula
D. Embryo
Answer:cB.cBlastocyst
Rationale:cAftercfertilizationcandccleavage,cthecballcofccellsc(morula)cformscintocacblastocyst
,cwhichcimplantscintocthecuterinecwall.
DIF:cEasy
TOP:cEmbryoniccdevelopmentc
MSC:cMultiplecChoice
3. Thecoralccavitycbeginsctocdevelopcduringcwhichcofcthecfollowingcstagescofcembryoniccd
evelopment?
A. Zygote
B. Fetal
C. Pre-implantation
D. Embryonic
Answer:cD.cEmbryonic
Rationale:cThecdevelopmentcofcthecoralccavitycstartscduringcthecembryoniccstage,caroundcth
ecthirdcweekcofcpregnancy,cascthecfacialcstructurescbeginctocform.
DIF:cModerate
TOP:cOralccavitycdevelopmentc
MSC:cMultiplecChoice
4. Thecprocesscbycwhichcthecneuralctubecformscandcbeginsctocdevelopcintocthecbraincandcsp
inalccordciscknowncas:
A. Gastrulation
B. Neurulation
C. Cleavage
D. Organogenesis
, Answer:cB.cNeurulation
Rationale:cNeurulationciscthecprocesscwherecthecneuralctubecforms,cwhichclatercgivescrisectoc
theccentralcnervouscsystemc(braincandcspinalccord).
DIF:cModerate
TOP:cNeuralcdevelopmentcMS
C:cMultiplecChoice
5. Whichcofcthecfollowingciscthecprimarycfunctioncofcthecmesodermclayercincembryoniccd
evelopment?
A. Formationcofcthecnervouscsystem
B. Developmentcofcthecskincandchair
C. Formationcofcmuscles,cbones,candccirculatorycsystems
D. Formationcofcthecdigestivecsystem
Answer:cC.cFormationcofcmuscles,cbones,candccirculatorycsystems
Rationale:cThecmesodermclayercgivescrisectocstructurescsuchcascmuscles,cbones,candctheccirculato
rycsystemcduringcembryoniccdevelopment.
DIF:cModeratecTOP
:cGermclayers
MSC:cMultiplecChoice
6. Thectermc"histology"crefersctocthecstudycof:
A. Thecstructurecandcfunctioncofctissues
B. Thecdevelopmentcofcorgans
C. Thecstructurecofccells
D. Thecdevelopmentcofcembryos
Answer:cA.cThecstructurecandcfunctioncofctissues
Rationale:cHistologyciscthecstudycofctissues,cincludingctheircstructurecandcfunction,candctheir
crolecincthecbody.
DIF:cEasyc TOP
:cHistology
MSC:cMultiplecChoice
7. Thecenamelcofcthectoothciscderivedcfromcwhichcembryonicctissue?
A. Ectoderm
B. Mesoderm
C. Endoderm
D. Neuralccrest
Answer:cA.cEctoderm
Rationale:cEnamel,cthechardcoutercsurfacecofcthectooth,cdevelopscfromcthecectodermalclayerc
ofcthecembryo.
DIF:cModerate
TOP:cToothcdevelopmentcMSC
:cMultiplecChoice
8. Thecdevelopmentcofcthecfacecandcoralccavitycduringcembryoniccdevelopmentcinvolvescf
usioncofcwhichcstructures?
A. Palatalcshelves
B. Maxillarycandcmandibularcprocesses
C. Frontalcnasalcprocess
D. BothcBcandcC
, Answer:cD.cBothcBcandcC
Rationale:cThecdevelopmentcofcthecfacecandcoralccavitycinvolvescthecfusioncofcthecmaxillary
candcmandibularcprocesses,cascwellcascthecfrontalcnasalcprocess.
DIF:cModerate
TOP:cFacialcdevelopmentcMSC
:cMultiplecChoice
9. Whichcstructureciscresponsiblecforcthecformationcofcthecteethcduringcembryoniccd
evelopment?
A. Neuralccrest
B. Ectoderm
C. Mesoderm
D. Endoderm
Answer:cA.cNeuralccrest
Rationale:cThecneuralccrestccellscplaycaccrucialcrolecincthecformationcofcthecteethcduringcembryoni
ccdevelopment.
DIF:cModerate
TOP:cToothcformationc
MSC:cMultiplecChoice
10. Thecfirstcindicationcofctoothcdevelopmentcoccurscduringcwhichcweekcofcembryoniccd
evelopment?
A. 2ndcweek
B. 5thcweek
C. 6thcweek
D. 7thcweek
Answer:cC.c6thcweek
Rationale:cThecfirstcindicationcofctoothcdevelopmentcappearscduringcthec6thcweekcofcembry
oniccdevelopment,cwhencthecdentalclaminacforms.
DIF:cModerate
TOP:cToothcdevelopmentcMSC
:cMultiplecChoice
11. Thecprocesscofcossificationcreferscto:
A. Thecformationcofcbloodccells
B. Thecformationcofcbone
C. Thecdevelopmentcofcthecskin
D. Thecdevelopmentcofcthecdigestivecsystem
Answer:cB.cThecformationcofcbone
Rationale:cOssificationciscthecprocesscbycwhichcbonectissueciscformedcfromccartilagecorcothe
rcconnectivectissue.
DIF:cModerate
TOP:cBonecdevelopmentc
MSC:cMultiplecChoice
12. Whichcofcthecfollowingciscackeycfeaturecofcthechistologicalcstructurecofcenamel?
A. Itcisccomposedcofccollagencfibers
B. Itciscavascularcandchascnoclivingccells
C. Itccontainscmanycbloodcvessels
D. Itchascachighccontentcofcwater