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Microbiology Lab 8 Questions with Correct
Answers | Updated (100% Correct Answers)
antimicrobials Answer: any compounds that kill or inhibit
microorganisms
antibiotics Answer: antimicrobials, usually of low molecular weight,
naturally produced by microorganisms to inhibit or kill other
microorganisms
ex. penicillin and streptomycin
semi-synthetics Answer: antimicrobials that are chemically
synthesized in the laboratory and are not produced by microbial
biosynthesis at all
ex. sulfa drugs
healthcare acquired infections (HAIs) Answer: formerly nosocomial
infections; acquired in hospitals; MRSA is responsible for many
hospital infections
Kirby-Bauer method Answer: used to determine the sensitivity or
resistance of a bacterium to an antimicrobial
performed by streaking a standardized inoculum of the test
organism on Mueller-Hinton medium, and then paper disks
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, 2
containing specific concentrations of an antimicrobial are deposited
on the agar surface. The antimicrobial diffuses out from the disk
into the agar, forming a concentration gradient. If the agent inhibits
or kills the test organism, there will be a zone around the disk
where no growth occurs, called the zone of inhibition.
Mueller-Hinton II agar is the recommended medium with pH
between 7.2 and 7.4
zone of inhibition Answer: the zone around the disk where no
growth occurs if an agents inhibits the microorganism; affected by
diffusibility of the agent, size of the inoculum, the type of medium,
and other factors
antiseptics Answer: substances such as alcohol or betadine that
inhibit microbial growth or kill microorganisms but they are gentle
enough to be applied to living tissue; do not destroy endospores
disinfectants Answer: chemical agents that are applied to inanimate
objects such as floors, walls, and tabletops to kill microorganisms;
damaging to living tissue
sterilants; sporocides Answer: destroy all microbial life, including
endospores
ex. ethylene oxide
© 2025 All rights reserved
Microbiology Lab 8 Questions with Correct
Answers | Updated (100% Correct Answers)
antimicrobials Answer: any compounds that kill or inhibit
microorganisms
antibiotics Answer: antimicrobials, usually of low molecular weight,
naturally produced by microorganisms to inhibit or kill other
microorganisms
ex. penicillin and streptomycin
semi-synthetics Answer: antimicrobials that are chemically
synthesized in the laboratory and are not produced by microbial
biosynthesis at all
ex. sulfa drugs
healthcare acquired infections (HAIs) Answer: formerly nosocomial
infections; acquired in hospitals; MRSA is responsible for many
hospital infections
Kirby-Bauer method Answer: used to determine the sensitivity or
resistance of a bacterium to an antimicrobial
performed by streaking a standardized inoculum of the test
organism on Mueller-Hinton medium, and then paper disks
© 2025 All rights reserved
, 2
containing specific concentrations of an antimicrobial are deposited
on the agar surface. The antimicrobial diffuses out from the disk
into the agar, forming a concentration gradient. If the agent inhibits
or kills the test organism, there will be a zone around the disk
where no growth occurs, called the zone of inhibition.
Mueller-Hinton II agar is the recommended medium with pH
between 7.2 and 7.4
zone of inhibition Answer: the zone around the disk where no
growth occurs if an agents inhibits the microorganism; affected by
diffusibility of the agent, size of the inoculum, the type of medium,
and other factors
antiseptics Answer: substances such as alcohol or betadine that
inhibit microbial growth or kill microorganisms but they are gentle
enough to be applied to living tissue; do not destroy endospores
disinfectants Answer: chemical agents that are applied to inanimate
objects such as floors, walls, and tabletops to kill microorganisms;
damaging to living tissue
sterilants; sporocides Answer: destroy all microbial life, including
endospores
ex. ethylene oxide
© 2025 All rights reserved
