MMBIO 221 EXAM 2 ROBISON STUDY GUIDE ACTUAL 2025/2026

Content Preview

MMBIO 221 EXAM 2 ROBISON STUDY GUIDE ACTUAL 2025/2026 QUESTIONS AND 100% CORRECT ANSWERS Disinfection - Answer -destruction of vegetative pathogens; usually on inanimate objects. Antiseptic - Answer -agent which prevents bact. contamination and growth; usually on living tissue. Which agent doesn't necessarily work better at higher concentrations? - Answer -Alcohol, 70% (goldie lock zone)(60-80% most effective) (Ethyl and Isopropyl) -Alcohol is very effective to resistant to inactivation by organic materials (halogens are not good at this) Name the factors that affect a disinfectant activity. - Answer --Contact Time: longer, the more effective. -Temperature: higher, the more effective. (moist heat better) -pH: depends on chemical; some synergy. -Bioburden: more microbes = longer time. -Types of Microbes: mycobacteria & spores are more difficult to kill. -Extraneous matter: organic matter inhibits many disinfectants. Need assistance on Online classes, Exams & Assignments? Reach out for instant help!! Full Course Assistance, Plagiarism-free Essay Writing, Research Paper, Dissertation, Discussion Posts, etc…. Confidential & Secure services. Tutors are available for all subjects! Email now at: tutorjean01@gmail.com -Proper Exposure: ensure agent gets in. -Disinfectant concentration: higher = better - exception with the alcohols. 2 types of antimicrobials - Answer -1. Alteration of cell walls 2. Interference with protein and nucleic acid structure What 3 organisms are used in the AOAC Use-Dilution test? - Answer --Staphylococcus aureus -Pseudomonas aeruginosa -Salmonella choleraesuis How to compute D values (decimal reduction time)- Answer --Time required to kill 90% (1 log) at a specific temperature. -killed 3 logs in 3 mins = 1 min is the D value Ionizing radiation - Answer -High energy Small wavelength (<1nm) Electron beams, gamma, xray -Creating ions -Disrupt H bonds -Oxidize dble covalent bonds -Create Hydroxyl radicals (denature DNA) -Microbes are much more resistant to ionizing radiation than multicellular organisms Non Ionizing radiation - Answer -Low energy Large wavelength (>1nm) UV (for air, clear fluid, surfaces) Need assistance on Online classes, Exams & Assignments? Reach out for instant help!! Full Course Assistance, Plagiarism-free Essay Writing, Research Paper, Dissertation, Discussion Posts, etc…. Confidential & Secure services. Tutors are available for all subjects! Email now at: tutorjean01@gmail.com