Medical Bacteriology Exam Questions
and Answers 100% Solved
T/F Mycobacterium species incorporate mycolic acid (a waxy substance) in
their cell walls, which makes them resistant to antibiotics. - ✔✔True, the
high lipid content fights against hydrophilic antibiotics.
T/F The presence of teichoic acid molecules in the cell wall produces a net
negative charge on the surface of Gram-positive bacteria. - ✔✔True it plays
important role in cell wall integrity, shape, & cell division rates.
T/F You can only find 70S ribosomes in prokaryotes, not in eukaryotes. -
✔✔True, 80S ribosomes are found in eukaryotes.
T/F N-acetylglucosamine (NAG) and N-acetylmuramic acid are synthesized
and attached to amino acids in the cytoplasm. - ✔✔True it happens in the
cytoplasmic phase of peptidoglycan synthesis.
What is the 1st E of the EESMDO? - ✔✔Encounter : the agent meets the
host system.
What is the 2nd E of the EESMDO? - ✔✔Entry : The agent enters the host
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,What is S of the EESMDO? - ✔✔Spread : The agent spreads from the site
of entry.
What is M of the EESMDO? - ✔✔Multiplication : The agent multiplies in the
host
What is D of the EESMDO? - ✔✔Damage : The agent, the host response,
or both cause tissue damage.
What is O of the EESMDO? - ✔✔Outcome : The agent or the host wins
out, or they learn to coexist.
T/F Most motile bacteria use flagella, but few of them use cilia for their
motility. - ✔✔False bacteria don't have cilia.
T/F Opportunistic pathogens are ones that do not normally cause disease
but can do so under certain circumstances. - ✔✔True, hey are due to
immune systems being compromised and use of antibiotics.
T/F All prokaryotes have a single chromosomes. - ✔✔False, there are
some that have 2 and some have 3.
T/F There shouldn't be any normal flora in blood, cerebrospinal fluid,
synovial fluid, or deep tissue. - ✔✔True, these areas should be sterile
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,T/F About 90 percent of normal flora can be removed by through washing,
but they grow back to near-normal numbers w/n 48 hours. - ✔✔False. It is
90%, but they grow back within 8 hours.
T/F Beta lactam antibiotics are least toxic to humans. - ✔✔True because
humans do not have cell walls in their cells.
T/F Endogenously acquired diseases are from agents present in or on the
body. - ✔✔True
T/F The bacterial outer membrane is permeable to most antibiotics. -
✔✔False, gram negative cells are more difficult for antibiotics to work.
T/F Treponema pallidum can transverse the placenta thus damaging the
fetus. - ✔✔False, the ones that effect the placenta are rubella, syphilis,
HIV, or cytomegalovirus.
T/F When we are healthy, the number of microbial cells in or on our body is
10 times less than the number of human cells we are made of. - ✔✔False
they are 10 more than regular human cells.
Which of the following does not differentiate Gram-positive from Gram
negative organisms?
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, (a) After iodine treatment, Gram positive retains crystal violet versus Gram
negative does not retain crystal violet.
(b) No outer membrane outside cell wall versus outer membrane outside
cell wall.
(c) Presence of polysaccharide versus absence of polysaccharide.
(d) Thick peptidoglycan versus thin peptidoglycan. - ✔✔(c) Presence of
polysaccharide versus absence of polysaccharide.
Fungi infections are difficult to treat because.
(a) Fungal and human cells are very similar.
(b) fungal cells have an impermeable spore coat.
(c) fungi are not susceptible to any drugs.
(d) fungal cells lack a cell membrane. - ✔✔(a) Fungal and human cells are
very similar.
Why is penicillin almost completely nontoxic to human cells?
(a) dosages are timed so that toxicity cannot develop.
(b) it targets cell membranes.
(c) it targets peptidoglycan that does not exist in humans.
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©NINJANERD 2025/2026. YEAR PUBLISHED 2025.
and Answers 100% Solved
T/F Mycobacterium species incorporate mycolic acid (a waxy substance) in
their cell walls, which makes them resistant to antibiotics. - ✔✔True, the
high lipid content fights against hydrophilic antibiotics.
T/F The presence of teichoic acid molecules in the cell wall produces a net
negative charge on the surface of Gram-positive bacteria. - ✔✔True it plays
important role in cell wall integrity, shape, & cell division rates.
T/F You can only find 70S ribosomes in prokaryotes, not in eukaryotes. -
✔✔True, 80S ribosomes are found in eukaryotes.
T/F N-acetylglucosamine (NAG) and N-acetylmuramic acid are synthesized
and attached to amino acids in the cytoplasm. - ✔✔True it happens in the
cytoplasmic phase of peptidoglycan synthesis.
What is the 1st E of the EESMDO? - ✔✔Encounter : the agent meets the
host system.
What is the 2nd E of the EESMDO? - ✔✔Entry : The agent enters the host
1
©NINJANERD 2025/2026. YEAR PUBLISHED 2025.
,What is S of the EESMDO? - ✔✔Spread : The agent spreads from the site
of entry.
What is M of the EESMDO? - ✔✔Multiplication : The agent multiplies in the
host
What is D of the EESMDO? - ✔✔Damage : The agent, the host response,
or both cause tissue damage.
What is O of the EESMDO? - ✔✔Outcome : The agent or the host wins
out, or they learn to coexist.
T/F Most motile bacteria use flagella, but few of them use cilia for their
motility. - ✔✔False bacteria don't have cilia.
T/F Opportunistic pathogens are ones that do not normally cause disease
but can do so under certain circumstances. - ✔✔True, hey are due to
immune systems being compromised and use of antibiotics.
T/F All prokaryotes have a single chromosomes. - ✔✔False, there are
some that have 2 and some have 3.
T/F There shouldn't be any normal flora in blood, cerebrospinal fluid,
synovial fluid, or deep tissue. - ✔✔True, these areas should be sterile
2
©NINJANERD 2025/2026. YEAR PUBLISHED 2025.
,T/F About 90 percent of normal flora can be removed by through washing,
but they grow back to near-normal numbers w/n 48 hours. - ✔✔False. It is
90%, but they grow back within 8 hours.
T/F Beta lactam antibiotics are least toxic to humans. - ✔✔True because
humans do not have cell walls in their cells.
T/F Endogenously acquired diseases are from agents present in or on the
body. - ✔✔True
T/F The bacterial outer membrane is permeable to most antibiotics. -
✔✔False, gram negative cells are more difficult for antibiotics to work.
T/F Treponema pallidum can transverse the placenta thus damaging the
fetus. - ✔✔False, the ones that effect the placenta are rubella, syphilis,
HIV, or cytomegalovirus.
T/F When we are healthy, the number of microbial cells in or on our body is
10 times less than the number of human cells we are made of. - ✔✔False
they are 10 more than regular human cells.
Which of the following does not differentiate Gram-positive from Gram
negative organisms?
3
©NINJANERD 2025/2026. YEAR PUBLISHED 2025.
, (a) After iodine treatment, Gram positive retains crystal violet versus Gram
negative does not retain crystal violet.
(b) No outer membrane outside cell wall versus outer membrane outside
cell wall.
(c) Presence of polysaccharide versus absence of polysaccharide.
(d) Thick peptidoglycan versus thin peptidoglycan. - ✔✔(c) Presence of
polysaccharide versus absence of polysaccharide.
Fungi infections are difficult to treat because.
(a) Fungal and human cells are very similar.
(b) fungal cells have an impermeable spore coat.
(c) fungi are not susceptible to any drugs.
(d) fungal cells lack a cell membrane. - ✔✔(a) Fungal and human cells are
very similar.
Why is penicillin almost completely nontoxic to human cells?
(a) dosages are timed so that toxicity cannot develop.
(b) it targets cell membranes.
(c) it targets peptidoglycan that does not exist in humans.
4
©NINJANERD 2025/2026. YEAR PUBLISHED 2025.
