MMBIO 221 ROBISON EXAM 2026 COMPLETE ALL
STRUCTURED
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED A+|BRAND
NEW!!
Main difference between disinfectants and antiseptics? - CORRECT ANSWER >>>Disinfectants
are used on inanimate objects; antiseptics are used on skin and tissue.
What agents don't necessarily work better at higher concentrations? - CORRECT ANSWER
>>>Alcohol agents.
Factors that affect a disinfectants activity? - CORRECT ANSWER >>>Contact Time (longer better)
Temperature (higher better)
pH
Bioburden (more microbes take longer)
Types of microbes (spores are more difficult to kill)
Extraneous matter (Organic matter inhibt many disinfectants)
Proper exposure (insure agents get in)
Disinfectant concentration (higher better)
3 Organisms used in AOAC Use-Dilution test? - CORRECT ANSWER >>>Staphylococcus aureus
Pseudomonos aeruginosa
Salmonella choleraesuis
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, How to compute D values? - CORRECT ANSWER >>>90% reduction in microbes or 1 log
reduction.
Ionizing Radiation - CORRECT ANSWER >>>< 1 nm wavelengths
Create ions by ejecting electrons from atoms .
Cause double-stranded breaks in DNA
Ionizing Radiation -- Electron Beams - CORRECT ANSWER >>>Effective at killing, but do not
penetrate well, used to sterilize some sliced meats and medical/dental supplies.
Ionizing Radiation -- Gamma Rays - CORRECT ANSWER >>>Penetrate well, but require hours to
kill microbes, used to sterilize meats, spices, and fresh fruits/vegetables.
Ionizing Radiation -- X-rays - CORRECT ANSWER >>>Require too much time to be practical for
growth control.
Non-ionizing (UV) - CORRECT ANSWER >>>> 1 nm wavelengths
Excites electrons and makes new covalent bonds
Suitable for disinfecting air, transparent fluids.
UV causes Thymine dimers in DNA
UV light doesn't penetrate well.
Anderson Samplers - CORRECT ANSWER >>>Air sampling devices that mirror the human
respiratory system.
Best agent for antimicrobial handwashing? - CORRECT ANSWER >>>4% chlorhexidine
2|Page
STRUCTURED
QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) |ALREADY GRADED A+|BRAND
NEW!!
Main difference between disinfectants and antiseptics? - CORRECT ANSWER >>>Disinfectants
are used on inanimate objects; antiseptics are used on skin and tissue.
What agents don't necessarily work better at higher concentrations? - CORRECT ANSWER
>>>Alcohol agents.
Factors that affect a disinfectants activity? - CORRECT ANSWER >>>Contact Time (longer better)
Temperature (higher better)
pH
Bioburden (more microbes take longer)
Types of microbes (spores are more difficult to kill)
Extraneous matter (Organic matter inhibt many disinfectants)
Proper exposure (insure agents get in)
Disinfectant concentration (higher better)
3 Organisms used in AOAC Use-Dilution test? - CORRECT ANSWER >>>Staphylococcus aureus
Pseudomonos aeruginosa
Salmonella choleraesuis
1|Page
, How to compute D values? - CORRECT ANSWER >>>90% reduction in microbes or 1 log
reduction.
Ionizing Radiation - CORRECT ANSWER >>>< 1 nm wavelengths
Create ions by ejecting electrons from atoms .
Cause double-stranded breaks in DNA
Ionizing Radiation -- Electron Beams - CORRECT ANSWER >>>Effective at killing, but do not
penetrate well, used to sterilize some sliced meats and medical/dental supplies.
Ionizing Radiation -- Gamma Rays - CORRECT ANSWER >>>Penetrate well, but require hours to
kill microbes, used to sterilize meats, spices, and fresh fruits/vegetables.
Ionizing Radiation -- X-rays - CORRECT ANSWER >>>Require too much time to be practical for
growth control.
Non-ionizing (UV) - CORRECT ANSWER >>>> 1 nm wavelengths
Excites electrons and makes new covalent bonds
Suitable for disinfecting air, transparent fluids.
UV causes Thymine dimers in DNA
UV light doesn't penetrate well.
Anderson Samplers - CORRECT ANSWER >>>Air sampling devices that mirror the human
respiratory system.
Best agent for antimicrobial handwashing? - CORRECT ANSWER >>>4% chlorhexidine
2|Page
