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