Microbiology MCQs (Quiz 8) Posted on June 8, 2026June 10, 2026Author agropublishers 0 1. _________________ ensures complete elimination of all microorganisms, including spores Sterilization Sanitization Disinfection Antisepsis 2. Joseph Lister concluded that surgical infections were caused by _________________ Spontaneous generation Bad air alone Microorganisms entering wounds Changes in body temperature 3. Alcohol is widely used as an intermediate-level disinfectant because it _____________ Sterilizes culture media Destroys all spores Replaces autoclaving Kills many vegetative microorganisms but not all spores 4. Eukaryotic 80S ribosomes consist of ________________ 40S and 60S subunits 30S and 60S subunits 20S and 60S subunits 30S and 50S subunits 5. Why is agar more suitable than gelatin for preparing solid culture media? Agar remains solid at incubation temperatures and is not easily degraded by bacteria Agar is cheaper than gelatin Agar contains antimicrobial compounds Agar is a better nutrient source 6. Many bacteria cannot use agar as a food source because they ______________ Lack cell walls Lack ribosomes Cannot absorb carbohydrates Lack enzymes capable of degrading agar 7. In microbiological studies, phenol was one of the earliest chemicals used as a _____________ Growth medium component Disinfectant Sterilizing agent Staining reagent 8. A microbiologist examining pigment production by bacterial colonies would benefit from agar’s ____________ Antimicrobial activity High melting point Nutritional value Transparency 9. The concept that microorganisms cause putrefaction and wound infections led Joseph Lister to introduce ____________________ Antibiotic therapy Vaccination Aseptic culturing Antiseptic surgery 10. Agar, a jelly-like substance used to solidify microbiological media, is classified as a _______________ Lipid Polysaccharide Nucleic acid Protein Loading … Question 1 of 10 Microbiology MCQs (Quiz 8)
