Bacteriology of Air MCQ Quiz | Environmental Microbiology

1. What is the primary source of microorganisms in the air of occupied rooms?

2. Which method for air sampling relies on gravitational settling of particles onto a culture plate?

3. The Andersen sampler is an example of which type of air sampling method?

4. Droplet nuclei, which can transmit diseases like tuberculosis, are typically what size?

5. Which of the following is an obligate intracellular bacterium often transmitted via aerosols from contaminated cooling towers?

6. HEPA filters are designed to remove what percentage of particles that are 0.3 micrometers in diameter?

7. The bacteriological quality of air in an operating theatre is crucial. Which of these is a common indicator organism for human contamination?

8. Which environmental factor has a significant natural bactericidal effect on airborne microorganisms?

9. *Bacillus anthracis* spores are a major bioterrorism concern due to their stability in aerosols. What is their primary characteristic that allows this?

10. The slit sampler is a device that collects airborne particles by:

11. Which term describes any suspension of fine solid or liquid particles in a gas?

12. A “bioaerosol” specifically refers to an aerosol containing:

13. In liquid impingement air sampling, what is a major disadvantage?

14. Which of the following bacteria is a common cause of hospital-acquired pneumonia transmitted through contaminated air and water systems?

15. The “colony forming unit” (CFU) is a measure used to estimate the number of:

16. Gram-positive bacteria, like *Micrococcus* and *Staphylococcus*, often dominate the air microbiota because they are more resistant to:

17. The primary mechanism of Ultraviolet Germicidal Irradiation (UVGI) is:

18. A patient develops a respiratory infection after being on a mechanical ventilator in the ICU. The air quality is suspected. This type of infection is best described as:

19. Which of the following is NOT a primary factor influencing the survival of microorganisms in the air?

20. The release of bacteria into the air from coughing or sneezing primarily forms:

21. Which part of the human respiratory tract is most effective at filtering out larger airborne particles (>10 µm)?

22. An outbreak of Q fever in a rural area is traced back to airborne transmission from infected livestock. What is the causative agent?

23. The “six-sieve” Andersen sampler is particularly useful in microbiology because it:

24. Which of these is a Gram-negative bacterium that can cause severe respiratory infections and is notoriously found in the air of environments inhabited by cystic fibrosis patients?

25. The concept of “laminar air flow” in operating rooms is designed to: