1. What is the primary mode of action of antibiotics against bacteria?
a. Disruption of cell membrane
b. Inhibition of protein synthesis
c. Inhibition of DNA replication
d. Activation of metabolic pathways
Answer: b. Inhibition of protein synthesis
2. Which of the following antibiotics is derived from a fungus?
a. Penicillin
b. Streptomycin
c. Tetracycline
d. Ciprofloxacin
Answer: a. Penicillin
3. What is the purpose of using a broad-spectrum antibiotic?
a. Targeting specific bacterial species
b. Treating viral infections
c. Treating a wide range of bacterial infections
d. Minimizing side effects
Answer: c. Treating a wide range of bacterial infections
4. How do bactericidal antibiotics differ from bacteriostatic antibiotics?
a. Bactericidal antibiotics inhibit cell wall synthesis, while bacteriostatic antibiotics disrupt cell membrane.
b. Bactericidal antibiotics kill bacteria, while bacteriostatic antibiotics inhibit their growth.
c. Bactericidal antibiotics inhibit protein synthesis, while bacteriostatic antibiotics inhibit DNA replication.
d. Bactericidal antibiotics and bacteriostatic antibiotics have the same mode of action.
Answer: b. Bactericidal antibiotics kill bacteria, while bacteriostatic antibiotics inhibit their growth.
5. What is the role of beta-lactamase in bacterial resistance to antibiotics like penicillin?
a. Facilitates antibiotic entry into bacterial cells
b. Inhibits bacterial cell wall synthesis
c. Degrades the antibiotic molecule
d. Stimulates bacterial metabolism
Answer: c. Degrades the antibiotic molecule
6. Which class of antibiotics inhibits the synthesis of bacterial cell walls?
a. Aminoglycosides
b. Macrolides
c. Cephalosporins
d. Penicillins
Answer: d. Penicillins
7. What is the primary target of fluoroquinolone antibiotics?
a. Cell membrane
b. Protein synthesis
c. DNA gyrase
d. RNA polymerase
Answer: c. DNA gyrase
8. Which of the following is an example of a tetracycline antibiotic?
a. Ampicillin
b. Erythromycin
c. Doxycycline
d. Ciprofloxacin
Answer: c. Doxycycline
9. What is the purpose of using combination therapy with multiple antibiotics?
a. Enhancing the effectiveness of individual antibiotics
b. Reducing the dosage of each antibiotic
c. Minimizing side effects
d. Treating viral infections
Answer: a. Enhancing the effectiveness of individual antibiotics
10. Which of the following is a potential consequence of antibiotic misuse or overuse?
a. Decreased bacterial resistance
b. Increased efficacy of antibiotics
c. Development of antibiotic-resistant strains
d. Enhanced antibiotic susceptibility
Answer: c. Development of antibiotic-resistant strains
11. Which antibiotic interferes with the synthesis of bacterial proteins by binding to the 30S subunit of the ribosome?
a. Penicillin
b. Streptomycin
c. Ciprofloxacin
d. Vancomycin
Answer: b. Streptomycin
12. What is the mechanism of action of sulfa drugs, a type of synthetic antibiotic?
a. Inhibition of cell wall synthesis
b. Disruption of cell membrane
c. Inhibition of DNA replication
d. Inhibition of folic acid synthesis
Answer: d. Inhibition of folic acid synthesis
13. Which of the following is commonly used as an antifungal antibiotic?
a. Tetracycline
b. Fluconazole
c. Ampicillin
d. Cephalexin
Answer: b. Fluconazole
14. What is the term for the ability of bacteria to survive exposure to an antibiotic that would normally be lethal to them?
a. Resistance
b. Susceptibility
c. Tolerance
d. Sensitivity
Answer: a. Resistance
15. What is the primary function of vancomycin, a glycopeptide antibiotic?
a. Inhibition of protein synthesis
b. Inhibition of cell wall synthesis
c. Inhibition of DNA replication
d. Disruption of cell membrane
Answer: b. Inhibition of cell wall synthesis
16. Which antibiotic is commonly used to treat Mycobacterium tuberculosis infections?
a. Cephalexin
b. Isoniazid
c. Tetracycline
d. Amoxicillin
Answer: b. Isoniazid
17. What is a major concern regarding the use of antibiotics in livestock farming?
a. Decreased bacterial resistance
b. Increased antibiotic efficacy
c. Development of antibiotic-resistant strains
d. Enhanced animal growth
Answer: c. Development of antibiotic-resistant strains
18. What is the primary target of polymyxin antibiotics?
a. Cell wall
b. Ribosomes
c. Cell membrane
d. DNA gyrase
Answer: c. Cell membrane
19. Which antibiotic class includes drugs like azithromycin and clarithromycin?
a. Aminoglycosides
b. Macrolides
c. Quinolones
d. Sulfonamides
Answer: b. Macrolides
20. What is the purpose of antibiotic sensitivity testing in the laboratory?
a. To determine the antibiotic resistance of bacteria
b. To identify the bacterial species
c. To assess the growth rate of bacteria
d. To measure the antibiotic concentration in the blood
Answer: a. To determine the antibiotic resistance of bacteria
21. Which of the following biosynthetic processes does an antibiotic impede in order to prevent cell-wall biosynthesis?
1. Cellulose
2. Lipopolysaccharide
3. Proteins
4. Peptidoglycans
Answer- Option (4) is correct.
22. Bacterial cells are transformed from rod-shaped to __________-shaped when they are cultured in a medium subjected to high osmotic pressure.
1. Spherical
2. Rod-shaped
3. Uneven
4. Elongated
Answer- Option (1) is correct.
23. Which of the following activities do polymyxins do to prevent the development of microbes?
1. Blockage of the formation of the cell wall
2. Damage to the cytoplasmic membrane
3. Blockage of the synthesis of nucleic acids and proteins
4. Blockage of certain enzyme systems
Answer- Option (2) is correct.
24. Tyrocidines have greater effectiveness against a) Gram-positive organisms
1. Gram-negative microbes
2. Mycoplasmas
3. Spirochetes
4. Gram Positive bacteria
Answer- Option (4) is correct.
25. Streptomyces rimosus produces the antibiotic known as _______________.
1. Chlortetracycline
2. Oxytetracycline
3. Tetracycline
4. Doxycycline
Answer- Option (2) is correct.
26. By joining forces with the ribosome’s 50S subunit, which of the following prevents protein synthesis?
1. Tetracycline
2. Chloramphenicol
3. Penicillin
4. Streptomycin
Answer- Option (2) is correct.
27. Which of the following techniques is best for measuring the effectiveness of antibiotics on bacteria?
1. Physical testing
2. Chemical testing
3. Biological testing
4. Combined physical and chemical testing
Answer- Option (2) is correct.
28. Which of the following antibiotics is most effective when added to the diet of pigs?
1. Aureomycin
2. Terramycin
3. Penicillin
4. Oxytetracycline
Answer- Option (4) is correct.
29. Which of the following types of antibiotics is anthramycin?
1. Antibacterial
2. Antifungal
3. Antitumor
4. Antiviral
Answer- Option (3) is correct.
30. Which of the following is an example of Neisseria gonorrhoeae being isolated by the application of certain antibiotics in media?
1. Selective Media
2. Differential Media
3. Enriched Media
4. Assay media
Answer- Option (1) is correct.
31. Which of the following antibiotics has less impact on dietary B12?
1. Streptomycin
2. Tetracycline
3. Anthramycin
4. Chloramphenicol
Answer- Option (1) is correct.
32. Which of the following substances interferes with protein synthesis, resulting in an antiviral effect?
1. Amantadine
2. Interferons
3. Acycloguanosine
4. 5′-iododeoxyuridine
Answer- Option (2) is correct.
33. Which of the following substances is added to ophthalmic solutions as a preservative?
1. Alcohol
2. Quaternary ammonium salts
3. Aldehydes
4. Phenol
Answer- Option (2) is correct.
34. Which of the following doesn’t influence penicillin’s ability to be effective?
1. Bile
2. Hydrochloric acid
3. Sodium hydroxide
4. Cysteine
Answer- Option (1) is correct.
35. Which antibiotic is produced by Streptomyces orientalis?
1. Cephalosporins
2. Cycloserine
3. Bacitracin
4. Vancomycin
Answer- Option (4) is correct.