Microbiology MCQs (Quiz 4) Posted on June 7, 2026June 10, 2026Author agropublishers 0 1. The genetic material in bacterial plasmids consists of ___________________ RNA Polysaccharide Circular DNA Protein 2. A laboratory technician sets the autoclave to 121°C for 15 minutes but forgets to close the exhaust valve. The most likely outcome is _____________________________________ Air is not completely removed, preventing steam from reaching 121°C, leading to failed sterilization Sterilization occurs faster because air helps heat transfer Effective sterilization, but a longer time is needed The autoclave explodes immediately 3. A Gram-positive bacterium is generally more susceptible to lysozyme because it possesses a ____________ Thin peptidoglycan layer Thick exposed peptidoglycan layer Protein capsule Thick outer membrane 4. The outermost layer of many bacterial capsules is predominantly _________________ Peptidoglycan Phospholipid Protein Polysaccharide 5. Which statement best explains why Robert Hooke’s observations were important to biology? He provided the first recorded description of cells, laying the foundation for cell theory He identified the process of cell division He discovered DNA within cells He proved that all cells contain nuclei 6. The scientist associated with antiseptic surgery is _________________ Alexander Fleming Edward Jenner Robert Brown Joseph Lister 7. In microbiology, chemotaxis refers to __________ Protein synthesis Cell division Capsule formation Movement in response to chemical stimuli 8. An antibiotic targets peptidoglycan synthesis. Which microbial structure will be most affected? Capsule Cell wall Ribosome Plasma membrane 9. Which of the following discoveries occurred during the golden age of microbiology (1857–1914)? First observation of bacteria by Leeuwenhoek Development of the germ theory of disease Discovery of DNA structure Discovery of penicillin 10. The plasma membrane mainly consists of _________________ Peptidoglycan Cellulose Chitin Phospholipids and proteins Loading … Question 1 of 10 Microbiology MCQs (Quiz 4)
