Microbiology MCQs (Quiz 12) Posted on June 9, 2026June 10, 2026Author agropublishers 0 1. Why is agar suitable for creating concentration gradients in microbiological media? It prevents diffusion completely Its gel matrix allows slow and controlled diffusion of molecules It rapidly circulates dissolved substances It destroys dissolved chemicals 2. ___________________________ is the substance that triggers an immune response Enzyme Hormone Antigen Antibody 3. A microbiologist needs to sterilize the nutrient agar before pouring plates. Which method should be used? Alcohol swabbing Autoclaving Boiling for 10 minutes Pasteurization 4. Primary function of the immune system includes ______________ Regulating body temperature Digesting food Transporting oxygen Distinguishing self from non-self and defending against pathogens 5. Viruses are considered acellular because they ____________ Lack proteins Are not composed of cells Lack genetic material Lack a plasma membrane 6. Bleach is effective against many microorganisms because it acts as a strong ______________ Oxidizing agent Nutrient source Buffering agent Reducing agent 7. _____________________ is a fungal structure specialized for nutrient absorption and anchorage Conidium Rhizoid Basidium Ascus 8. Why is the transparency of agar important in microbiological studies? It increases bacterial growth rates It sterilizes the culture medium It allows clear observation of colony characteristics and reactions It prevents contamination 9. Chlorination is primarily intended to _______________ Promote microbial growth Sterilize surgical instruments Prepare culture media Reduce waterborne pathogens 10. Iodine is most commonly used as a ___________________ Media sterilant Water disinfectant Skin antiseptic Surface sterilant Loading … Question 1 of 10 Microbiology MCQs (Quiz 12)
