6th k
Edition by Brian
k k
,Chapterk1:kFetalkLungkDevelopmentTestk
Bkank
MULTIPLEk CHOICE
1. Whichkofvthekfollowingkphasesvofvhumanklungkdevelopmentkiskcharacterizedkbykthekformationofkak c
apillaryknetworkkaroundkairwaykpassages?
a. Pseudoglandular
b. Saccular
c. Alveolar
d. Canalicular
ANS:vk D
Thekcanalicularkphasekfollowskthekpseudoglandularkphase,klastingkfromkapproximatelyk17kweek
sktok26kweekskofkgestation.kThiskphasekisksoknamedkbecausekofkthekappearancekofkvascularchannel
s,korkcapillaries,kwhichkbeginktokgrowkbykformingkakcapillaryknetworkkaroundkthek airkpassages.kDuri
nk gkthekpseudoglandularkstage,kwhichkbeginskatvdayk52kandkextendsktokweekk16kofkgestation,kthekai
krwayksystemksubdivideskextensivelykandkthekconductingkairwayksystemkdevelops,kendingkwithkthektk
erminalkbronchioles.kTheksaccularkstagekofvdevelopment,kwhichktakesvplacekfromkweeksk29ktok36kokfv
gestation,kiskcharacterizedkbykthekdevelopmentkofksacsvthatlaterkbecomekalveoli.kDuringktheksacckula
rkphase,kaktremendouskincreasekinkthekpotential
gas-
exchangingksurfacekareakoccurs.kThekdistinctionkbetweenktheksaccularkstagekandkthekalveolarksk
tagekiskarbitrary.kThekalveolarkstagekstretcheskfromk39kweekskofkgestationktokterm.Thiskstagekiskr
epresentedkbykthekestablishmentkofkalveoli.
REF:kpp.k 3-5
2. Regardingkpostnatalklungkgrowth,kbykapproximatelykwhatkagekdokmostkofkthekalveolikthatkwillbe
k presentkinktheklungskforklifekdevelop?
a. 6kmonths
b. 1kyear
c. 1.5kyears
d. 2kyears
ANS:vk C
Mostkofkthekpostnatalkformationkofvalveolikinkthekinfantvoccurskoverkthekfirstv1.5kyearskofklife.kAtk
2kyearskofkage,ktheknumberkofkalveolikvariesvsubstantiallykamongkindividuals.kAfterk2kyearsofka
ge,kmaleskhavekmorekalveolikthankdokfemales.kAfterkalveolarkmultiplicationkends,kthekalveolikcontin
uek tokincreasekinksizekuntilkthoracickgrowthkiskcompleted.
REF:kp.k6
3. Thekrespiratoryktherapistkiskevaluatingkaknewbornkwithkmildkrespiratorykdistresskduektoktrachealstek
nosis.kDuringkwhichkperiodkofvlungkdevelopmentkdidkthiskproblemkdevelop?
a. Embryonal
b. Saccular
c. Canalicular
d. Alveolar
ANS:vkA
k
, Thekinitialkstructureskofkthekpulmonaryktreekdevelopkduringkthekembryonalkstage.kErrorskinkdevelokpm
entkduringkthisvtimekmaykresultkinklaryngeal,ktracheal,korkesophagealkatresiakorkstenosis.kPulmoknaryk
hypoplasia,kankincompletekdevelopmentkofktheklungskcharacterizedkbykanabnormallyklowknkumbe
rkand/orksizekofkbronchopulmonaryksegmentskand/orkalveoli,kcankdevelopkduringkthekpseukdoglan
dularkphase.kIfkthekfetuskiskbornkduringkthekcanalicularkphasek(i.e.,vprematurely),kseverekrekspiratoryk
distresskcankbekexpectedkbecausekthekinadequatelykdevelopedkairways,kalongkwithkinskufficientka
ndkimmatureksurfactantkproductionkbykalveolarktypekIIkcells,kgiveskrisektokthekconstellatikonkofkprobl
emskknownkaskinfantvrespiratorykdistressksyndrome.
REF:k p.k6
4. Whichkofkthekfollowingkmechanismskisk(are)kresponsiblekforkthekpossiblekassociationkbetweenoligok
hydramnioskandklungkhypoplasia?
I. Abnormalkcarbohydratekmetabolism
II. Mechanicalkrestrictionkofkthekchestkwall
III. Interferencekwithkfetalkbreathing
IV. Failurektokproducekfetalklungkliquid
a. IkandkIIIkonly
b. IIkandkIIIkonly
c. I,kII,kandkIVkonly
d. II,vIII,kandkIVkonly
ANS:vk D
Oligohydramnios,kakreducedkquantitykofkamniotickfluidkpresentkforkankextendedkperiodkofktime,
withk ork withoutk renalk anomTalEieSs,Tv isBvaA sNsoKciSatEeLdw
LEithRl. uCnO
g vM
hypoplasia. k Thek mechanismsvbyk whichk amniotick flu
kidkvolume kinfluencesklung kgrowthkremainkunclear. kPossiblekexplanationskfor
reducedkquantitykofkamniotickfluidkincludekmechanicalkrestrictionkofkthekchestkwall,kinterferencekwkit
hkfetalkbreathing,korkfailurektokproducekfetalklungkliquid.kThesekclinicalkandkexperimentalkobserk
vationskpossiblykpointktokakcommonkdenominator,klungkstretch,kaskbeingkamajorkgrowthkstimulant.
REF:kpp.k6-7
5. WhatkisvthekpurposekofktheksubstanceksecretedkbykthektypekIIkpneumocyte?
a. Tokincreasekthekgaskexchangeksurfacekarea
b. Tokreduceksurfacektension
c. Tokmaintainklungkelasticity
d. Tokpreservekthekvolumekofkthekamniotickfluid
ANS:vk B
Thekprimarykrolekofkmammalianksurfactantkisktoklowerktheksurfacektensionkwithinkthekalveolus,kspecifk
icallykatkthekair–
liquidkinterface.kThiskallowsvthekdelicatekstructurekofkthekalveolusktokexpandkwhenkfilledkwithkair.kWkit
houtksurfactant,kthekalveoluskremainskcollapsedkbecausekofkthehighksurfacektensionkofkthekmoistkalkv
eolarksurface.kSurfactantkisvcomposedkpredominantlykofkankintricatekblendkofkphospholipids,vneutk ra
lklipids,kandkproteins.
REF:kp.k8
, 6. Whichkofkthekfollowingktestsvofkthekamniotickfluidkhavekbeenkshownktokbeksensitivekindicatorsofklunk
gkmaturity?
a. Levelskofkprednisone
b. Levelskofk epidermalk growthk factor
c. Levelskofkprostaglandins
d. Levelskofkphosphatidylglycerol k andkphosphatidylcholine
ANS:vk D
Ofclinicalkrelevancekduringklatekgestation,kanalysiskofkamniotickfluidkforkthekconcentrationkofphoskp
hatidylglycerolkandkphosphatidylcholinekhaskbeenkshownktokbekaksensitivekindicatorkofkthekstatek of
kfetalklungkmaturity.
REF:kp.k8
7. Approximatelyk howkmuchkfetalklungkfluidkisksecretedk daily?
a. Aboutk150ktok200kml
b. Aboutk250ktok300kml
c. Aboutk350ktok400kml
d. Aboutk450ktok500kml
ANS:kB
Fetalklungskareksecretorykorganskthatkmakekbreathing-
likekmovementskbutkserveknokrespiratorykfunctionkbeforekbirth.kTheyksecretekab
outk250ktok300kmlkofkliquidkperkday.
8. Theklungkbudkemergeskfromkwhichkofkthekfollowingkstructures?
a. Thekpharynx
b. Thekforegut
c. Thekmesenchyme
d. Thektubularkepithelium
ANS:kA
Thekembryonalkphasekincludeskprimitiveklungkdevelopmentkandkiskgenerallykregardedktokencompasskthekfirstv2
k monthskofkgestation.
Theklungkbeginsktokemergekaskakbudkfromkthekpharynxk26kdayskafterkconception.
Edition by Brian
k k
,Chapterk1:kFetalkLungkDevelopmentTestk
Bkank
MULTIPLEk CHOICE
1. Whichkofvthekfollowingkphasesvofvhumanklungkdevelopmentkiskcharacterizedkbykthekformationofkak c
apillaryknetworkkaroundkairwaykpassages?
a. Pseudoglandular
b. Saccular
c. Alveolar
d. Canalicular
ANS:vk D
Thekcanalicularkphasekfollowskthekpseudoglandularkphase,klastingkfromkapproximatelyk17kweek
sktok26kweekskofkgestation.kThiskphasekisksoknamedkbecausekofkthekappearancekofkvascularchannel
s,korkcapillaries,kwhichkbeginktokgrowkbykformingkakcapillaryknetworkkaroundkthek airkpassages.kDuri
nk gkthekpseudoglandularkstage,kwhichkbeginskatvdayk52kandkextendsktokweekk16kofkgestation,kthekai
krwayksystemksubdivideskextensivelykandkthekconductingkairwayksystemkdevelops,kendingkwithkthektk
erminalkbronchioles.kTheksaccularkstagekofvdevelopment,kwhichktakesvplacekfromkweeksk29ktok36kokfv
gestation,kiskcharacterizedkbykthekdevelopmentkofksacsvthatlaterkbecomekalveoli.kDuringktheksacckula
rkphase,kaktremendouskincreasekinkthekpotential
gas-
exchangingksurfacekareakoccurs.kThekdistinctionkbetweenktheksaccularkstagekandkthekalveolarksk
tagekiskarbitrary.kThekalveolarkstagekstretcheskfromk39kweekskofkgestationktokterm.Thiskstagekiskr
epresentedkbykthekestablishmentkofkalveoli.
REF:kpp.k 3-5
2. Regardingkpostnatalklungkgrowth,kbykapproximatelykwhatkagekdokmostkofkthekalveolikthatkwillbe
k presentkinktheklungskforklifekdevelop?
a. 6kmonths
b. 1kyear
c. 1.5kyears
d. 2kyears
ANS:vk C
Mostkofkthekpostnatalkformationkofvalveolikinkthekinfantvoccurskoverkthekfirstv1.5kyearskofklife.kAtk
2kyearskofkage,ktheknumberkofkalveolikvariesvsubstantiallykamongkindividuals.kAfterk2kyearsofka
ge,kmaleskhavekmorekalveolikthankdokfemales.kAfterkalveolarkmultiplicationkends,kthekalveolikcontin
uek tokincreasekinksizekuntilkthoracickgrowthkiskcompleted.
REF:kp.k6
3. Thekrespiratoryktherapistkiskevaluatingkaknewbornkwithkmildkrespiratorykdistresskduektoktrachealstek
nosis.kDuringkwhichkperiodkofvlungkdevelopmentkdidkthiskproblemkdevelop?
a. Embryonal
b. Saccular
c. Canalicular
d. Alveolar
ANS:vkA
k
, Thekinitialkstructureskofkthekpulmonaryktreekdevelopkduringkthekembryonalkstage.kErrorskinkdevelokpm
entkduringkthisvtimekmaykresultkinklaryngeal,ktracheal,korkesophagealkatresiakorkstenosis.kPulmoknaryk
hypoplasia,kankincompletekdevelopmentkofktheklungskcharacterizedkbykanabnormallyklowknkumbe
rkand/orksizekofkbronchopulmonaryksegmentskand/orkalveoli,kcankdevelopkduringkthekpseukdoglan
dularkphase.kIfkthekfetuskiskbornkduringkthekcanalicularkphasek(i.e.,vprematurely),kseverekrekspiratoryk
distresskcankbekexpectedkbecausekthekinadequatelykdevelopedkairways,kalongkwithkinskufficientka
ndkimmatureksurfactantkproductionkbykalveolarktypekIIkcells,kgiveskrisektokthekconstellatikonkofkprobl
emskknownkaskinfantvrespiratorykdistressksyndrome.
REF:k p.k6
4. Whichkofkthekfollowingkmechanismskisk(are)kresponsiblekforkthekpossiblekassociationkbetweenoligok
hydramnioskandklungkhypoplasia?
I. Abnormalkcarbohydratekmetabolism
II. Mechanicalkrestrictionkofkthekchestkwall
III. Interferencekwithkfetalkbreathing
IV. Failurektokproducekfetalklungkliquid
a. IkandkIIIkonly
b. IIkandkIIIkonly
c. I,kII,kandkIVkonly
d. II,vIII,kandkIVkonly
ANS:vk D
Oligohydramnios,kakreducedkquantitykofkamniotickfluidkpresentkforkankextendedkperiodkofktime,
withk ork withoutk renalk anomTalEieSs,Tv isBvaA sNsoKciSatEeLdw
LEithRl. uCnO
g vM
hypoplasia. k Thek mechanismsvbyk whichk amniotick flu
kidkvolume kinfluencesklung kgrowthkremainkunclear. kPossiblekexplanationskfor
reducedkquantitykofkamniotickfluidkincludekmechanicalkrestrictionkofkthekchestkwall,kinterferencekwkit
hkfetalkbreathing,korkfailurektokproducekfetalklungkliquid.kThesekclinicalkandkexperimentalkobserk
vationskpossiblykpointktokakcommonkdenominator,klungkstretch,kaskbeingkamajorkgrowthkstimulant.
REF:kpp.k6-7
5. WhatkisvthekpurposekofktheksubstanceksecretedkbykthektypekIIkpneumocyte?
a. Tokincreasekthekgaskexchangeksurfacekarea
b. Tokreduceksurfacektension
c. Tokmaintainklungkelasticity
d. Tokpreservekthekvolumekofkthekamniotickfluid
ANS:vk B
Thekprimarykrolekofkmammalianksurfactantkisktoklowerktheksurfacektensionkwithinkthekalveolus,kspecifk
icallykatkthekair–
liquidkinterface.kThiskallowsvthekdelicatekstructurekofkthekalveolusktokexpandkwhenkfilledkwithkair.kWkit
houtksurfactant,kthekalveoluskremainskcollapsedkbecausekofkthehighksurfacektensionkofkthekmoistkalkv
eolarksurface.kSurfactantkisvcomposedkpredominantlykofkankintricatekblendkofkphospholipids,vneutk ra
lklipids,kandkproteins.
REF:kp.k8
, 6. Whichkofkthekfollowingktestsvofkthekamniotickfluidkhavekbeenkshownktokbeksensitivekindicatorsofklunk
gkmaturity?
a. Levelskofkprednisone
b. Levelskofk epidermalk growthk factor
c. Levelskofkprostaglandins
d. Levelskofkphosphatidylglycerol k andkphosphatidylcholine
ANS:vk D
Ofclinicalkrelevancekduringklatekgestation,kanalysiskofkamniotickfluidkforkthekconcentrationkofphoskp
hatidylglycerolkandkphosphatidylcholinekhaskbeenkshownktokbekaksensitivekindicatorkofkthekstatek of
kfetalklungkmaturity.
REF:kp.k8
7. Approximatelyk howkmuchkfetalklungkfluidkisksecretedk daily?
a. Aboutk150ktok200kml
b. Aboutk250ktok300kml
c. Aboutk350ktok400kml
d. Aboutk450ktok500kml
ANS:kB
Fetalklungskareksecretorykorganskthatkmakekbreathing-
likekmovementskbutkserveknokrespiratorykfunctionkbeforekbirth.kTheyksecretekab
outk250ktok300kmlkofkliquidkperkday.
8. Theklungkbudkemergeskfromkwhichkofkthekfollowingkstructures?
a. Thekpharynx
b. Thekforegut
c. Thekmesenchyme
d. Thektubularkepithelium
ANS:kA
Thekembryonalkphasekincludeskprimitiveklungkdevelopmentkandkiskgenerallykregardedktokencompasskthekfirstv2
k monthskofkgestation.
Theklungkbeginsktokemergekaskakbudkfromkthekpharynxk26kdayskafterkconception.
