Quiz

QUIZ

1. What is least likely to be a reason to use a bactericidal drug?

a. In an immunocompromised host b. With a particularly virulent organism c. When the organism isn’t known d. When the infection is life-threatening

Answer: c. Each of these is a situation in which a bactericidal drug is recommended; however, it is not necessarily recommended when the infection is not known.

2. Which type of antibiotic is generally chosen empirically when the causative organism isn’t known? a. Broad-spectrum b. Narrow-spectrum c. Bactericidal d. Bacteriostatic

Answer: a. A broad-spectrum antibiotic is often chosen when the causative agent isn’t known so that there is a greater chance of covering for the most probably organism in the infection.

3. What do the beta-lactam drugs have the most affect on with regard to antibacterial activity?

a. DNA synthesis b. Cell membrane c. Cell wall d. Metabolism

Answer: c. The beta-lactam antibiotic classification is one that acts directly on cell wall synthesis, which is something relatively unique to prokaryotes.

4. What part of the bacterial organism is most affected by vancomycin?

a. DNA synthesis b. Ribosomes c. ATP synthesis d. Cell wall

Answer: d. Vancomycin binds to the precursors of cell wall synthesis so it cannot be made. This is a bactericidal drug that is effective only in killing gram-positive organisms.

5. What adverse effect of chloramphenicol prevents its common usage in humans today?

a. Bone marrow suppression b. Kidney failure c. Neurotoxicity d. Cancer-causing effects

Answer: a. Chloramphenicol can cause aplastic anemia and other forms of bone marrow suppression so that it is not frequently used today as an antibiotic of choice.

6. What is the site of activity of drugs that block protein synthesis, such as aminoglycosides and tetracyclines?

a. Amino acid synthesis is blocked. b. Uptake of amino acids are blocked. c. Post-translational modification is blocked. d. There is prevention of the peptide bond formation.

Answer: d. These drugs will prevent the formation of the peptide bonds by binding to the different subunits of the ribosomes. Each drug has a slightly different effect on polypeptide synthesis.

7. What do most protozoal drugs like artemisinin and proguanil treat?

a. Ringworm b. Giardia c. Rickettsia d. Malaria

Answer: d. These drugs are particularly effective in the treatment of malaria, often used in combination in order to prevent resistances to these drugs.

8. What do drugs like mebendazole and albendazole treat?

a. Protozoans b. Helminths c. Viruses d. Fungi

Answer: b. These drugs treat helminthic infections by blocking microtubule formation in the intestinal lining cells of the helminth organism. This blocks glucose uptake by the organism.

9. What type of infection is most likely to be related to multidrug resistance?

a. Infections in the elderly b. Nosocomial infections c. Gram-positive infections d. Community-acquired infections

Answer: b. Nosocomial infections that occur in medical settings have the greatest risk of being caused by multidrug resistance because of the number of antimicrobial drugs used in these types of settings.

10. What will the Kirby-Bauer test determine?

a. The presence of a bactericidal versus a bacteriostatic drug b. The degree of virulence of an organism c. The presence of a possible effective antimicrobial organism d. The nutrients an organism needs to grow

Answer: c. The Kirby-Bauer test will be able to predict a possible presence of an effective antimicrobial agent.