1. Microbiology is the study of:
(A) Animals only
(B) Plants only
(C) Microorganisms
(D) Fungi only
2. Bacteria are classified as:
(A) Eukaryotes
(B) Prokaryotes
(C) Fungi
(D) Viruses
3. The study of viruses is called:
(A) Phycology
(B) Mycology
(C) Bacteriology
(D) Virology
4. Fungi are:
(A) Algae
(B) Prokaryotic organisms
(C) Viruses
(D) Eukaryotic organisms
5. The scientist who first observed microorganisms was:
(A) Alexander Fleming
(B) Louis Pasteur
(C) Robert Koch
(D) Antonie van Leeuwenhoek
6. Bacterial cell wall contains:
(A) Cellulose
(B) Peptidoglycan
(C) Chitin
(D) Starch
7. Gram-positive bacteria stain:
(A) Yellow
(B) Red
(C) Green
(D) Purple
8. Gram-negative bacteria stain:
(A) Purple
(B) Pink/Red
(C) Blue
(D) Brown
9. Bacteria reproduce mainly by:
(A) Binary fission
(B) Budding
(C) Spore formation
(D) Conjugation only
10. Endospores are:
(A) Resistant structures formed by some bacteria
(B) Only reproductive cells
(C) Only nutrient cells
(D) Only protein structures
11. The medium used to grow bacteria is called:
(A) Culture medium
(B) Soil
(C) Water
(D) Air
12. Pure culture contains:
(A) Multiple types
(B) Only one type of microorganism
(C) Only viruses
(D) Only fungi
13. The streak plate method is used for:
(A) Counting bacteria
(B) Isolating pure colonies
(C) Staining bacteria
(D) Observing motility
14. Aseptic technique prevents:
(A) Staining
(B) Growth
(C) Contamination
(D) Motility
15. Louis Pasteur is known for:
(A) Staining techniques
(B) Discovery of penicillin
(C) Germ theory of disease
(D) Pasteurization
16. Robert Koch is famous for:
(A) Pasteurization
(B) Vaccination development
(C) Postulates proving microorganisms cause disease
(D) Antibiotic discovery
17. Bacterial shapes include:
(A) Cocci, bacilli, spirilla
(B) Only cocci
(C) Only spirilla
(D) Only bacilli
18. Cocci are:
(A) Spiral bacteria
(B) Rod-shaped bacteria
(C) Spherical bacteria
(D) Filamentous bacteria
19. Bacilli are:
(A) Spiral bacteria
(B) Spherical bacteria
(C) Rod-shaped bacteria
(D) Star-shaped bacteria
20. Spirilla are:
(A) Filamentous bacteria
(B) Spherical bacteria
(C) Rod-shaped bacteria
(D) Spiral-shaped bacteria
21. Bacterial motility is facilitated by:
(A) Cilia
(B) Flagella
(C) Pseudopodia
(D) Pili only
22. Bacterial pili are used for:
(A) Movement only
(B) Conjugation and attachment
(C) Nutrition only
(D) Spore formation
23. Facultative anaerobes:
(A) Grow without oxygen only
(B) Require oxygen only
(C) Can grow with or without oxygen
(D) Are non-living
24. Obligate anaerobes:
(A) Are fungi only
(B) Require oxygen
(C) Can tolerate both
(D) Cannot survive in the presence of oxygen
25. Obligate aerobes:
(A) Require oxygen to grow
(B) Do not need oxygen
(C) Can grow with or without oxygen
(D) Are viruses only
26. Autotrophic bacteria obtain energy from:
(A) Air only
(B) Organic food only
(C) Water only
(D) Sunlight (photoautotrophs) or chemicals (chemoautotrophs)
27. Heterotrophic bacteria obtain energy from:
(A) Organic matter
(B) Sunlight
(C) Minerals
(D) Air only
28. Antibiotics are produced by:
(A) Animals only
(B) Plants only
(C) Microorganisms like bacteria and fungi
(D) Viruses only
29. Penicillin is produced by:
(A) E. coli bacteria
(B) Streptococcus bacteria
(C) Penicillium fungi
(D) Aspergillus fungi
30. Microbial fermentation is used in:
(A) Only sugar refining
(B) Only meat production
(C) Only soap production
(D) Yogurt, cheese, and alcohol production
31. Lactic acid bacteria are used in:
(A) Antibiotic production only
(B) Beer only
(C) Yogurt and cheese production
(D) Vinegar production only
32. Microorganisms that can survive extreme conditions are called:
(A) Pathogens
(B) Extremophiles
(C) Commensals
(D) Saprophytes
33. Thermophiles grow best at:
(A) High temperatures
(B) Low temperatures
(C) Neutral temperatures
(D) Only in air
34. Psychrophiles grow best at:
(A) High temperatures
(B) Low temperatures
(C) Neutral temperatures
(D) Only in soil
35. Halophiles grow best in:
(A) Acidic soil only
(B) Low salt
(C) Freshwater only
(D) High salt concentrations
36. Microbial pathogens cause:
(A) Water purification only
(B) Plant growth
(C) Photosynthesis
(D) Infectious diseases
37. Endotoxins are:
(A) Toxins produced by fungi
(B) Toxins released from bacterial cell walls
(C) Toxins produced by viruses
(D) Toxins in water only
38. Exotoxins are:
(A) Toxins in plants only
(B) Toxins inside spores
(C) Toxins in soil
(D) Toxins secreted by bacteria
39. Microbial biofilms are:
(A) Free-floating microbes only
(B) Communities of microorganisms attached to surfaces
(C) Viruses only
(D) Fungi only
40. Koch’s postulates are used to:
(A) Identify plants
(B) Establish the causative agent of disease
(C) Produce antibiotics
(D) Ferment milk
41. Normal microbiota refers to:
(A) Viruses only
(B) Pathogens only
(C) Fungi only
(D) Microorganisms naturally present in the body
42. Microorganisms used in sewage treatment are called:
(A) Algae only
(B) Pathogens only
(C) Decomposers
(D) Protozoa only
43. Bacteriophages are:
(A) Viruses that infect humans only
(B) Viruses that infect bacteria
(C) Fungi
(D) Algae
44. Microbial transformation of organic matter into methane is called:
(A) Nitrification
(B) Fermentation
(C) Photosynthesis
(D) Methanogenesis
45. Antibiotic resistance occurs due to:
(A) Genetic mutations and misuse of antibiotics
(B) Proper antibiotic use only
(C) Vaccination only
(D) Filtration only
46. Aseptic techniques include:
(A) Only using gloves
(B) Only washing hands
(C) Only feeding microbes
(D) Sterilization of tools and working under clean conditions
47. Anaerobic bacteria grow in:
(A) Both oxygen and air
(B) Presence of oxygen only
(C) Absence of oxygen
(D) Only sunlight
48. Microbial nitrogen fixation converts:
(A) Ammonia into nitrogen only
(B) Atmospheric nitrogen into ammonia
(C) Nitrogen into nitrate only
(D) Proteins into amino acids
49. Microbes in biotechnology are used for:
(A) Only water filtration
(B) Only soil formation
(C) Only plant growth
(D) Antibiotics, enzymes, vaccines, and fermentation
50. General microbiology is important for:
(A) Only agriculture
(B) Medicine, industry, agriculture, and environment
(C) Only industry
(D) Only medicine