MICR 2420 Final Exam UPDATED
QUESTIONS AND CORRECT ANSWERS
What is a biofilm? - CORRECT ANSWER Complex assemblies of microbial communities
attached to surfaces surrounded by a sticky and adhesive extracellular polysaccharide (EPS) matrix
Microbes that are part of a biofilm are said to be... - CORRECT ANSWER Highly resistant to
antimicrobials
What is quorum sensing? - CORRECT ANSWER A mechanism for regulating assessing
bacterial density and regulating density-dependent community behaviours
How is quorum sensing achieved in biofilms? - CORRECT ANSWER Autoinducers that are
secreted in the surrounding environment
What happens to biofilms once nutrients become scarce? - CORRECT ANSWER Individuals
detach from the community to forage for new nutrient sources or die entirely
What is selective toxcicity in the context of antibiotics? - CORRECT ANSWER The ability of a
drug to harm or kill a target organism without causing signficiant harm to the host organism
What aspects of bacterial cell physiology do antibiotics typically target? - CORRECT
ANSWER Cell wall, cell membranes, DNA, RNA, and protein synthesis
What makes developing antiviral drugs more challenging than developing antibiotics? - CORRECT
ANSWER Viruses have high and rapid mutation rates leading to drug resistance and changes in
viral structure; hard to acheive selective toxcicity and must be extremely precicse to avoid damaging
human cells; viral latency;
How are resistance genes spread? - CORRECT ANSWER Horizontal gene transfer
(conjugation, transformation, transduction)
,What are the four main antibiotic resistance strategies? - CORRECT ANSWER Keep
antibiotics out of the cell; prevent antibiotics from binding their target; dislodging an antibiotic
already bound to its target
What are the three ways antibiotics can be kept out of the cell? - CORRECT
ANSWER Destroyed before entering; decrease membrane permeability (narrow pore
expression); pump the antibiotic out of the cell using specific transporters
What are the two ways to prevent antibiotics from binding their target? - CORRECT
ANSWER Modify the target so it no longer has the ability to bind the antibiotic; add modifying
groups to the antibiotic to deactivate it
How can an antibiotic be disloged if it's already bound to its target? - CORRECT
ANSWER Creation of proteins that bind to ribosomes
Beta-lactamases - CORRECT ANSWER Enzymes that inactivate beta-lactam antibiotics.
Beta lactamase mechanism - CORRECT ANSWER Hydrolyzes the Beta-lactam ring,
deactivating the antibiotic
What practices underlie our problem of extensive antibiotic resistance? - CORRECT
ANSWER Agricultural uses
Antibiotics can... (context of microbiome) - CORRECT ANSWER Disrupt and lead to
secondary infections
What is antibiotic stewardship? - CORRECT ANSWER Promoting appropriate use of
antibiotics
Acquisition of immunity - CORRECT ANSWER Natural and artificial (both ether actively or
passively)
Inactivated vaccines - CORRECT ANSWER Contain a dead version of the pathogen
, Benefits and drawbacks of inactivated vaccines - CORRECT ANSWER Easy to produce;
complete inactivation can be difficult to achieve and don't provide long lasting immunity
Live-attenuated vaccines - CORRECT ANSWER Contain a weakened version of the pathogen
Benefits and drawbacks of live-attenuated vaccines - CORRECT ANSWER Appropriate
pathogen infection process; difficult to produce, not suited for immunocompromised individuals,
usually requie CC distribution
Subunit, recombinant, polysaccharide, and conjugate vaccines - CORRECT ANSWER Use
specific pieces of the pathogen like a protein, sugar, or its casing
Benefits and drawbacks of subunit, recombinant, polysaccharide, and conjugate vaccines - CORRECT
ANSWER Easy to produce and no chance of infection; can be hard to find a protective antigen
What are toxoid vaccines? - CORRECT ANSWER Use a toxin made by the pathogen that
causes a disease, creating an immunity only to the parts of the pathogen that cause disease rather than
the pathogen itself
When is an antigen considered good/effective? - CORRECT ANSWER When they are
highly/easily visible to the immune system, don't mutate easily, and provide long-lasting immunity
Nucleic acid vaccines - CORRECT ANSWER Use genetic material wrapped in a lipid layer to
instruct cells to produce an antigen that triggers an immune response
What are three key features of nucleic acid vaccines? - CORRECT ANSWER Do not use a live
virus, mRNA is broken down quickly by the body, fast to design and manufacture
Why is it good that foreign mRNA of nucleic acid vaccines is broken down quickly by the body? -
CORRECT ANSWER A FOREIGN body would not remain in your body for very long
Benefits and drawbacks of nucelic acid vaccines - CORRECT ANSWER Easy to manufacture
and release into the market with no chance of infection; CC distribution required, poor public
understanding/fear mongering
QUESTIONS AND CORRECT ANSWERS
What is a biofilm? - CORRECT ANSWER Complex assemblies of microbial communities
attached to surfaces surrounded by a sticky and adhesive extracellular polysaccharide (EPS) matrix
Microbes that are part of a biofilm are said to be... - CORRECT ANSWER Highly resistant to
antimicrobials
What is quorum sensing? - CORRECT ANSWER A mechanism for regulating assessing
bacterial density and regulating density-dependent community behaviours
How is quorum sensing achieved in biofilms? - CORRECT ANSWER Autoinducers that are
secreted in the surrounding environment
What happens to biofilms once nutrients become scarce? - CORRECT ANSWER Individuals
detach from the community to forage for new nutrient sources or die entirely
What is selective toxcicity in the context of antibiotics? - CORRECT ANSWER The ability of a
drug to harm or kill a target organism without causing signficiant harm to the host organism
What aspects of bacterial cell physiology do antibiotics typically target? - CORRECT
ANSWER Cell wall, cell membranes, DNA, RNA, and protein synthesis
What makes developing antiviral drugs more challenging than developing antibiotics? - CORRECT
ANSWER Viruses have high and rapid mutation rates leading to drug resistance and changes in
viral structure; hard to acheive selective toxcicity and must be extremely precicse to avoid damaging
human cells; viral latency;
How are resistance genes spread? - CORRECT ANSWER Horizontal gene transfer
(conjugation, transformation, transduction)
,What are the four main antibiotic resistance strategies? - CORRECT ANSWER Keep
antibiotics out of the cell; prevent antibiotics from binding their target; dislodging an antibiotic
already bound to its target
What are the three ways antibiotics can be kept out of the cell? - CORRECT
ANSWER Destroyed before entering; decrease membrane permeability (narrow pore
expression); pump the antibiotic out of the cell using specific transporters
What are the two ways to prevent antibiotics from binding their target? - CORRECT
ANSWER Modify the target so it no longer has the ability to bind the antibiotic; add modifying
groups to the antibiotic to deactivate it
How can an antibiotic be disloged if it's already bound to its target? - CORRECT
ANSWER Creation of proteins that bind to ribosomes
Beta-lactamases - CORRECT ANSWER Enzymes that inactivate beta-lactam antibiotics.
Beta lactamase mechanism - CORRECT ANSWER Hydrolyzes the Beta-lactam ring,
deactivating the antibiotic
What practices underlie our problem of extensive antibiotic resistance? - CORRECT
ANSWER Agricultural uses
Antibiotics can... (context of microbiome) - CORRECT ANSWER Disrupt and lead to
secondary infections
What is antibiotic stewardship? - CORRECT ANSWER Promoting appropriate use of
antibiotics
Acquisition of immunity - CORRECT ANSWER Natural and artificial (both ether actively or
passively)
Inactivated vaccines - CORRECT ANSWER Contain a dead version of the pathogen
, Benefits and drawbacks of inactivated vaccines - CORRECT ANSWER Easy to produce;
complete inactivation can be difficult to achieve and don't provide long lasting immunity
Live-attenuated vaccines - CORRECT ANSWER Contain a weakened version of the pathogen
Benefits and drawbacks of live-attenuated vaccines - CORRECT ANSWER Appropriate
pathogen infection process; difficult to produce, not suited for immunocompromised individuals,
usually requie CC distribution
Subunit, recombinant, polysaccharide, and conjugate vaccines - CORRECT ANSWER Use
specific pieces of the pathogen like a protein, sugar, or its casing
Benefits and drawbacks of subunit, recombinant, polysaccharide, and conjugate vaccines - CORRECT
ANSWER Easy to produce and no chance of infection; can be hard to find a protective antigen
What are toxoid vaccines? - CORRECT ANSWER Use a toxin made by the pathogen that
causes a disease, creating an immunity only to the parts of the pathogen that cause disease rather than
the pathogen itself
When is an antigen considered good/effective? - CORRECT ANSWER When they are
highly/easily visible to the immune system, don't mutate easily, and provide long-lasting immunity
Nucleic acid vaccines - CORRECT ANSWER Use genetic material wrapped in a lipid layer to
instruct cells to produce an antigen that triggers an immune response
What are three key features of nucleic acid vaccines? - CORRECT ANSWER Do not use a live
virus, mRNA is broken down quickly by the body, fast to design and manufacture
Why is it good that foreign mRNA of nucleic acid vaccines is broken down quickly by the body? -
CORRECT ANSWER A FOREIGN body would not remain in your body for very long
Benefits and drawbacks of nucelic acid vaccines - CORRECT ANSWER Easy to manufacture
and release into the market with no chance of infection; CC distribution required, poor public
understanding/fear mongering
