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MMG 301 Exam 3 Questions with Correct
Answers | Updated (100% Correct Answers)
Transpeptidase, the enzyme that cross-links peptidoglycan in
bacterial cell walls Answer: β-lactam target
Weakens cell wall → lysis due to osmotic pressure Answer: Effect of
β-lactams on bacteria
β-lactam ring Answer: Structure defining all β-lactams
Enzyme that cleaves β-lactam rings → antibiotic inactivation
Answer: NDM-1 function
Enzymatic degradation of antibiotic Answer: Resistance mechanism
of NDM-1
Encodes PBP2a, a transpeptidase that does not bind β-lactams
Answer: MecA function
High MIC value Answer: How to identify resistance on an E-test
Low MIC value Answer: How to identify sensitivity on an E-test
Measures DNA amount in real time through amplification Answer:
qPCR purpose
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Growth-independent, does not require live bacteria Answer: qPCR
dependency
Low starting DNA amount Answer: High CT value meaning
Number of microbes that kill 50% of hosts Answer: LD50 definition
Number of microbes that infect 50% of hosts Answer: ID50
definition
More virulence → lower LD50 Answer: Effect of virulence on LD50
More virulence → lower ID50 Answer: Effect of virulence on ID50
Breaks down collagen to aid tissue invasion Answer: Collagenase
function
Compares bacterial DNA by separating large fragments Answer:
PFGE purpose
Determines if isolates are the same strain Answer: PFGE in
outbreaks
Ingest bacteria → they grow in the body Answer: Food infection
Ingest pre-formed toxin Answer: Food poisoning
Nutrient deprivation or extreme stress Answer: Trigger for
sporulation
© 2025 All rights reserved
MMG 301 Exam 3 Questions with Correct
Answers | Updated (100% Correct Answers)
Transpeptidase, the enzyme that cross-links peptidoglycan in
bacterial cell walls Answer: β-lactam target
Weakens cell wall → lysis due to osmotic pressure Answer: Effect of
β-lactams on bacteria
β-lactam ring Answer: Structure defining all β-lactams
Enzyme that cleaves β-lactam rings → antibiotic inactivation
Answer: NDM-1 function
Enzymatic degradation of antibiotic Answer: Resistance mechanism
of NDM-1
Encodes PBP2a, a transpeptidase that does not bind β-lactams
Answer: MecA function
High MIC value Answer: How to identify resistance on an E-test
Low MIC value Answer: How to identify sensitivity on an E-test
Measures DNA amount in real time through amplification Answer:
qPCR purpose
© 2025 All rights reserved
, 2
Growth-independent, does not require live bacteria Answer: qPCR
dependency
Low starting DNA amount Answer: High CT value meaning
Number of microbes that kill 50% of hosts Answer: LD50 definition
Number of microbes that infect 50% of hosts Answer: ID50
definition
More virulence → lower LD50 Answer: Effect of virulence on LD50
More virulence → lower ID50 Answer: Effect of virulence on ID50
Breaks down collagen to aid tissue invasion Answer: Collagenase
function
Compares bacterial DNA by separating large fragments Answer:
PFGE purpose
Determines if isolates are the same strain Answer: PFGE in
outbreaks
Ingest bacteria → they grow in the body Answer: Food infection
Ingest pre-formed toxin Answer: Food poisoning
Nutrient deprivation or extreme stress Answer: Trigger for
sporulation
© 2025 All rights reserved
