BIOLl271l /l BIOL271l Modulel 3:l (Latestl
2026/l 2027l Update)l 100%l Verifiedl
Questionsl &l Answersl |l Gradel A
Q:l Identifyl whatl typel ofl electronl microscopel wasl usedl tol capturel thel
followingl imagel andl explainl yourl choice.l (Studyl alll images)
Answer:
Thel abovel imagel isl capturedl vial al Transmissionl Electronl Microscopel
(TEM).l Evenl atl 20nml resolutionl (insetl image),l subcellularl substructuresl arel
stilll visible.l Thel imagel lacksl thel outsidel 'shell'l onlyl appearancel ofl SEM.
Q:l Gram-Positivel cellsl appearl _______l inl colorl duel tol al ______l
peptidoglycanl layerl inl thel celll wall.
Answer:
purple,l thick
Q:l Gram-Negativel cellsl appearl _______l inl colorl duel tol al ______l
peptidoglycanl layerl inl thel celll wall.
Answer:
pink,l thin
,Q:l Truel orl False:l Followingl thel decolorizationl stepl ofl thel Graml stain,l
Gram-Negativel bacterial willl appearl colorless
Answer:
True.l Evenl together,l thel LPSl andl thinl peptidoglycanl layerl arel unablel tol
retainl thel crystall violetl dyel duringl decolorization.
Q:l Namel onel substancel capablel ofl chemicallyl fixingl cellsl tol al slide.
Answer:
Anyl ofl thel followingl arel true:l Paraformaldehyde,l ethanoll orl methanol.
Q:l Youl wantl tol observel thel sizel andl shapel ofl al cell.l Whatl isl thel easiestl
stainingl techniquel thatl youl couldl perform?l Namel atl leastl onel dyel youl
wouldl usel duringl thisl process.
Answer:
Simplel stain.l Youl couldl usel anyl ofl thel following:l methylenel blue,l crystall
violet,l safraninl orl fuschin.
Q:l Youl suspectl al patientl mayl havel TB.l Oncel al samplel hasl beenl
obtainedl itl isl sentl offl tol thel labl forl anl acid-fastl stain.l Ifl thel patientl werel
infectedl withl TB,l describel whatl youl wouldl expectl tol seel onl thel stainedl
slide.
, Answer:
Youl wouldl expectl tol seel redl cellsl (TB+)l onl al bluel backgroundl (TBl
negative).
Q:l Truel orl False:l Ifl al patientl isl suspectedl ofl havingl malaria,l al Giemsal
stainl wouldl bel anl appropriatel differentiall testl tol perform.
Answer:
True.l Giemsal stainsl arel oftenl usedl inl thel clinicall settingl tol aidl inl thel
diagnosisl ofl bloodl parasites.
Q:l Whichl ofl thel followingl couldl bel seenl clearlyl byl thel unaidedl eye?l
Selectl alll thatl apply.
A.l Bacterial withl diameterl ofl 24l μm
B.l Protozoal withl diameterl ofl 150l μm
C.l Virusl withl al diameterl ofl 0.2l μm
D.l Skinl celll withl diameterl ofl 1500l μm
Answer:
B.l Protozoal withl diameterl ofl 150l μm
D.l Skinl celll withl diameterl ofl 1500l μm
Thel unaidedl eyel can,l onl average,l clearlyl resolvel objectsl >l 100l μm
2026/l 2027l Update)l 100%l Verifiedl
Questionsl &l Answersl |l Gradel A
Q:l Identifyl whatl typel ofl electronl microscopel wasl usedl tol capturel thel
followingl imagel andl explainl yourl choice.l (Studyl alll images)
Answer:
Thel abovel imagel isl capturedl vial al Transmissionl Electronl Microscopel
(TEM).l Evenl atl 20nml resolutionl (insetl image),l subcellularl substructuresl arel
stilll visible.l Thel imagel lacksl thel outsidel 'shell'l onlyl appearancel ofl SEM.
Q:l Gram-Positivel cellsl appearl _______l inl colorl duel tol al ______l
peptidoglycanl layerl inl thel celll wall.
Answer:
purple,l thick
Q:l Gram-Negativel cellsl appearl _______l inl colorl duel tol al ______l
peptidoglycanl layerl inl thel celll wall.
Answer:
pink,l thin
,Q:l Truel orl False:l Followingl thel decolorizationl stepl ofl thel Graml stain,l
Gram-Negativel bacterial willl appearl colorless
Answer:
True.l Evenl together,l thel LPSl andl thinl peptidoglycanl layerl arel unablel tol
retainl thel crystall violetl dyel duringl decolorization.
Q:l Namel onel substancel capablel ofl chemicallyl fixingl cellsl tol al slide.
Answer:
Anyl ofl thel followingl arel true:l Paraformaldehyde,l ethanoll orl methanol.
Q:l Youl wantl tol observel thel sizel andl shapel ofl al cell.l Whatl isl thel easiestl
stainingl techniquel thatl youl couldl perform?l Namel atl leastl onel dyel youl
wouldl usel duringl thisl process.
Answer:
Simplel stain.l Youl couldl usel anyl ofl thel following:l methylenel blue,l crystall
violet,l safraninl orl fuschin.
Q:l Youl suspectl al patientl mayl havel TB.l Oncel al samplel hasl beenl
obtainedl itl isl sentl offl tol thel labl forl anl acid-fastl stain.l Ifl thel patientl werel
infectedl withl TB,l describel whatl youl wouldl expectl tol seel onl thel stainedl
slide.
, Answer:
Youl wouldl expectl tol seel redl cellsl (TB+)l onl al bluel backgroundl (TBl
negative).
Q:l Truel orl False:l Ifl al patientl isl suspectedl ofl havingl malaria,l al Giemsal
stainl wouldl bel anl appropriatel differentiall testl tol perform.
Answer:
True.l Giemsal stainsl arel oftenl usedl inl thel clinicall settingl tol aidl inl thel
diagnosisl ofl bloodl parasites.
Q:l Whichl ofl thel followingl couldl bel seenl clearlyl byl thel unaidedl eye?l
Selectl alll thatl apply.
A.l Bacterial withl diameterl ofl 24l μm
B.l Protozoal withl diameterl ofl 150l μm
C.l Virusl withl al diameterl ofl 0.2l μm
D.l Skinl celll withl diameterl ofl 1500l μm
Answer:
B.l Protozoal withl diameterl ofl 150l μm
D.l Skinl celll withl diameterl ofl 1500l μm
Thel unaidedl eyel can,l onl average,l clearlyl resolvel objectsl >l 100l μm
