Examl 3:l BIOl 205/l BIO205l (Latestl 2025/l
2026l Update)l Microbiologyl Guide|l Questionsl &l Answers|l Gradel A|l 100%l Correctl (Verifiedl Solutions)-l GCU
Q:l Patternl recognitionl receptorsl (PRRs)
Answer:
proteinsl onl orl inl cellsl thatl detectl pathogenl associatedl molecularl patternsl (PAMPs),l signsl ofl invasion
Q:l Toll-likel receptorsl (TLRs)
Answer:
anchoredl inl thel membranesl ofl sentinell cells -detectl specificl microbs
Q:l Complementl system
Answer:
-Activatesl thel adaptivel immunel system -Al groupl ofl interatingl seruml proteinsl thatl providel al nonspecificl defensel mechanis -Alternative,l lectin,l andl classicall pathwayl intersectl atl C3
Q:l Complementl system
Answer:
-Classicall Pathway:l Triggeredl byl antibodiesl boundl tol pathogens.
-Alternativel Pathway:l Activatesl directlyl onl pathogenl surfaces.
-Lectinl Pathway:l Initiatedl byl proteinsl bindingl tol sugarsl onl pathogens.
Q:l Opsonization
Answer:
coatingl antigenl withl antibodyl enhancesl phagocytosis
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Q:l C5b
Answer:
bindsl withl complementl proteinsl tol forml thel membranel attackl complexesl (MAC)
Q:l Whatl killl al microbe
Answer:
Phagolysosome
Q:l Fourl cardinall signsl ofl inflammation
Answer:
-heat -pain -redness
-swelling:l lossl ofl function
Q:l Apoptosis
Answer:
programmedl celll death;l doesl notl triggerl inflammatoryl response
Q:l Fever
Answer:
-Strongl indicatorl ofl infectiousl disease -inhibitsl bacteriall growthl andl speedsl upl thel body'sl reactions
Q:l Pyrogens
Answer:
whatl arel cellsl producel inl responsel tol fever
Q:l Emill vonl Behring
Answer:
-Injectedl diphtherial toxinl intol guineal pigsl thatl hadl recoveredl froml diphtheria;l theyl didl notl getl ill -suggestedl somethingl inl theirl bloodl protectedl them:l antitoxins 2 / 4
Q:l Secondaryl response
Answer:
-strongerl responsel tol re-exposurel tol pathogen -responsel hasl molecularl specificity
Q:l primaryl lymphoidl organs
Answer:
bonel marrowl andl thymus -producel lymphocytes
Q:l Secondaryl lymphoidl function
Answer:
-sitesl wherel lymphocytesl gatherl tol encounterl antigens -facilitatel interactionsl betweenl cells
Q:l Secondaryl lymphoidl organs
Answer:
lymphl nodes,l spleen,l tonsils,l adenoids,l appendix
Q:l Lymphocytes
Answer:
-Tl cellsl andl Bl cells -maturel whenl cellsl havel specificl receptorl proteinsl onl surface
Q:l Bl lymphocytesl orl Bl cells
Answer:
differentiatel into -plasmal cellsl thatl producel antibodies -Memoryl Bl cellsl thatl storyl thel antigenl informationl andl usedl inl 2ndl response
Q:l Tl lymphocytesl orl Tl cells
Answer: 3 / 4
-havel T-celll receptorsl (TCR)
differentiatel into:
-Cytotoxicl Tl cellsl -Helperl Tl cells
Q:l T-celll receptorsl (TCR)
Answer:
dol notl recognizel freel antigensl andl mustl bel presentedl byl thel body'sl ownl cellsl calledl MHCl (Majorl Histocompatibilityl Complex)
Q:l Regulatoryl Tl cells
Answer:
preventl immunel systeml froml attackingl "self"l molecules
Q:l Majorl Histocompatibilityl Complexl (MHC)
Answer:
Onl surfacel ofl cell -presentl anitgensl tol T-celll receptorsl (TCR)l onl Tl cells
Q:l Classl Il MHCl proteins
Answer:
-foundl onl alll cellsl inl body
Q:l Classl IIl MHCl proteins
Answer:
-foundl onlyl onl al fewl typesl ofl cellsl suchl asl macrophages,l Bl cellsl andl activatedl Tl cells
Q:l Cytotoxicl Tl cells
Answer:
Respondl tol endogenousl antigensl presentedl onl thel MHCl classl Il moleculesl -CD8
Q:l Helperl Tl cells
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