Portage Microbiology Exam #6 Questions And Correct Answers

PORTAGE MICROBIOLOGY EXAM #6
QUESTIONS AND CORRECT
ANSWERS
TrueA2orA2False:A2BecauseA2theA2genomeA2isA2containedA2withinA2anA2enclosedA2space,A2
(muchA2likeA2theA2nucleusA2ofA2aA2cell)A2virusesA2areA2classifiedA2asA2eukaryoticA2-A2Ans--
False.A2VirusesA2areA2neitherA2eukaryoticA2norA2prokaryotic

DescribeA2theA2twoA2basicA2componentsA2ofA2aA2virusA2(shortA2answer)A2-A2Ans--
AA2virusA2hasA21.A2genomicA2materialA2comprisedA2ofA2eitherA2DNAA2orA2RNAA2andA22.A2a
A2capsid,A2aA2membrane-
likeA2protectiveA2structureA2thatA2containsA2theA2geneticA2material,A2similarA2toA2theA2nucle
usA2ofA2aA2eukaryoticA2cell

TheA2_____A2surroundsA2theA2capsidA2ofA2someA2virusesA2-A2Ans--Envelope

TheA2envelopeA2surroundsA2theA2_____A2ofA2someA2virusesA2-A2Ans--Capsid

TrueA2orA2False:A2YouA2wouldA2expectA2toA2seeA2aA2viralA2envelopeA2onA2aA2virusA2infectin
gA2aA2plantA2cellA2-A2Ans--
False.A2TheA2overwhelmingA2majorityA2ofA2animalA2virusesA2areA2envelopedA2whereasA2th
eA2majorityA2ofA2plantA2orA2bacteria-infectingA2virusesA2areA2not

TrueA2orA2False:A2YouA2wouldA2expectA2toA2seeA2aA2viralA2envelopeA2onA2aA2virusA2infectin
gA2aA2bacterialA2cellA2-A2Ans--False:A2NotA2allA2theA2virusesA2haveA2envelopes

RankA2theA2followingA2virusesA2basedA2onA2theirA2sizeA2fromA2largestA2toA2smallest:A2ortho
myxovirus,A2poliovirus,A2variolavirusA2-A2Ans--Variolavirus>Orthomyxovirus>Poliovirus

RankA2theA2followingA2virusesA2basedA2onA2theirA2sizeA2fromA2largestA2toA2smallest:Param
yxovirus,A2Poliovirus,A2SmallpoxA2virusA2-A2Ans--Smallpox>Paramyxovirus>Poliovirus

TrueA2orA2False:A2ViralA2replicationA2occursA2afterA2itA2attachesA2andA2entersA2theA2hostA2c
ellA2-A2Ans--
True.A2TheA2viralA2genomeA2isA2neverA2replicatedA2beforeA2attachmentA2andA2entry

TrueA2orA2False:A2HighlyA2infectiousA2virusesA2undergoA2genomeA2replicationA2priorA2toA2v
iralA2attachmentA2andA2entry.A2-A2Ans--
False.A2TheA2viralA2genomeA2isA2neverA2replicatedA2beforeA2attachmentA2andA2entryA2rega
rdlessA2ofA2itsA2levelA2ofA2infectivity.

, PlaceA2theA2followingA2viralA2lifeA2cycleA2stepsA2inA2orderA2beginningA2withA2viralA2attachm
entA2andA2provideA2aA2descriptionA2ofA2eachA2stepA2(shortA2answer)A2-A2Ans--
Uncoating:A2theA2viralA2capsidA2disassembles
Release:A2NewA2virusA2particlesA2areA2producedA2andA2leaveA2theA2cell
Replication:A2theA2viralA2genomeA2isA2theA2'blueprint'A2toA2makeA2copiesA2ofA2itself
Attachment:A2viralA2receptorsA2bindA2toA2hostA2proteinsA2onA2theA2surfaceA2ofA2theA2cell
Entry:A2theA2virusA2fusesA2withA2theA2hostA2membraneA2andA2entersA2theA2cell
NewA2Infection:A2newlyA2producedA2virusesA2thatA2leftA2theA2hostA2cellA2nowA2goA2onA2toA2i
nfectA2newA2cells

AA2virusA2thatA2infectsA2bacteriaA2isA2calledA2aA2_____A2andA2containsA2aA2_____A2-
sideA2polygonA2capsidA2(fillA2inA2theA2blank)A2-A2Ans--Bacteriophage;A220-sided

TrueA2orA2False:A2StructurallyA2bacteriophagesA2areA2similarA2toA2virusesA2thatA2infectA2an
imalsA2-A2Ans--False.A2BacteriophagesA2haveA2aA2distinctA2compositionA2andA2structure

TrueA2orA2False.A2Structurally,A2bacteriophagesA2areA2distinctA2fromA2virusesA2thatA2infect
A2plantA2orA2animalA2cells.A2-A2Ans--
True.A2BacteriophagesA2areA2structurallyA2distinctA2fromA2virusesA2thatA2infectA2plantA2and
A2animalsA2cells.


IdentifyA2theA2followingA2componentsA2ofA2aA2bacteriophageA2(picture)A2-A2Ans--
1.A2Capsid
2.A2Collar
3.A2Tail
4.A2Base
5.A2TailA2fibers

DescribeA2theA2mainA2differencesA2betweenA2lyticA2andA2temperateA2phagesA2(shortA2ans
wer)A2-A2Ans--
LyticA2bacteriophagesA2replicateA2withinA2theA2hostA2bacteriaA2untilA2itA2ruptures,A2wherea
sA2temperateA2phagesA2primarilyA2existA2inA2aA2non-
replicativeA2stateA2thatA2doesA2notA2killA2theA2hostA2cell

LyticA2phagesA2replicateA2allA2viralA2proteinsA2neededA2forA2theA2assemblyA2ofA2newA2virus
A2particlesA2whereasA2lysogenicA2phageA2genomesA2areA2integratedA2intoA2theA2hostA2gen
omeA2butA2productionA2ofA2viralA2proteinsA2isA2suppressed

BasedA2onA2theA2followingA2image,A2wouldA2youA2expectA2theA2viralA2titerA2toA2beA2highA2o
rA2low?A2Why?A2(cloudy)A2-A2Ans--
Low.A2AsA2turbidityA2isA2aA2functionA2ofA2theA2numberA2ofA2intactA2bacterialA2cellsA2present
A2inA2theA2media,A2theA2amountA2ofA2virusA2containedA2withinA2theA2aboveA2tubeA2mustA2b
eA2low.A2AsA2theA2lyticA2continuesA2moreA2andA2moreA2bacterialA2cellsA2willA2beA2destroye
d,A2effectivelyA2clearingA2theA2media.

WhichA2ofA2theA2followingA2cannotA2beA2spreadA2viaA2airborneA2particles