B.Pharm. Bachelor of Pharmacy Microbiology & Immunology 2 — Questions and Answers
Question 1: Which type of culture media supports the growth of most non-fastidious bacteria?
- Selective media
- Enrichment media
- Differential media
- General purpose (nutrient) media (Correct answer)
Correct answer: General purpose (nutrient) media
General purpose media like nutrient agar or tryptic soy agar provide basic nutritional requirements to support the growth of most non-fastidious bacteria.
Question 2: Endotoxins are components of which bacterial cell structure?
- Gram-positive cell wall peptidoglycan
- Gram-negative outer membrane lipopolysaccharide (LPS) (Correct answer)
- Bacterial capsule
- Flagellar protein
Correct answer: Gram-negative outer membrane lipopolysaccharide (LPS)
Endotoxins are lipopolysaccharide (LPS) molecules found in the outer membrane of Gram-negative bacteria, released upon cell lysis and causing fever and septic shock.
Question 3: Which sterilization method is most suitable for heat-labile pharmaceutical solutions?
- Dry heat sterilization (160°C)
- Autoclaving (121°C)
- Filtration through 0.22 μm membrane (Correct answer)
- UV radiation
Correct answer: Filtration through 0.22 μm membrane
Membrane filtration through 0.22 μm filters removes microorganisms from heat-sensitive solutions without exposing them to high temperatures.
Question 4: MIC (Minimum Inhibitory Concentration) is defined as the lowest concentration of an antibiotic that:
- Kills 99% of bacteria
- Prevents visible bacterial growth (Correct answer)
- Prevents biofilm formation
- Is non-toxic to human cells
Correct answer: Prevents visible bacterial growth
MIC is the lowest concentration of an antimicrobial agent that inhibits visible bacterial growth in a standardized susceptibility test.
Question 5: Which immune cells are primarily responsible for cell-mediated immunity against intracellular pathogens?
- B lymphocytes
- Neutrophils
- CD8+ cytotoxic T lymphocytes (Correct answer)
- Mast cells
Correct answer: CD8+ cytotoxic T lymphocytes
CD8+ cytotoxic T lymphocytes recognize and kill cells infected with intracellular pathogens (viruses, certain bacteria) by releasing perforin and granzymes.
Question 6: The LAL (Limulus Amebocyte Lysate) test is used in pharmaceutical quality control to detect:
- Heavy metal contamination
- Bacterial endotoxins (pyrogens) (Correct answer)
- Fungal contamination
- Viral particles
Correct answer: Bacterial endotoxins (pyrogens)
The LAL test uses lysate from horseshoe crab blood cells to detect bacterial endotoxins (LPS) in parenteral pharmaceutical products.
B.Pharm. Bachelor of Pharmacy Microbiology & Immunology 2
Which type of culture media supports the growth of most non-fastidious bacteria?