Question 1

Which of the following best describes how Alexander Fleming discovered penicillin in 1928?

Accepted Answer

He noticed that a mold growing on a petri dish inhibited the growth of Staphylococcus bacteria.

Question 2

Why are broad-spectrum antibiotics more likely to disrupt the normal microbiota than narrow-spectrum antibiotics?

Accepted Answer

Broad-spectrum antibiotics inhibit a wide range of bacteria, including beneficial ones.

Question 3

Which of the following is an example of a narrow-spectrum antibiotic?

Accepted Answer

Penicillin G

Question 4

A patient is prescribed a broad-spectrum antibiotic for a respiratory infection. What is a potential risk associated with this treatment?

Accepted Answer

Disruption of normal microbiota leading to secondary infections such as $$	extit{Clostridioides difficile}$$

Question 5

Which of the following best defines selective toxicity in antimicrobial drugs?

Accepted Answer

The ability of a drug to target microbial cells without harming host cells

Question 6

Which mechanism is most commonly used by bacteria to develop resistance to antibiotics?

Accepted Answer

Producing enzymes that inactivate the drug, such as $$\beta-$$lactamase

Question 7

Which of the following is an example of an antibiotic that inhibits cell wall synthesis?

Accepted Answer

Penicillin

Question 8

Which of the following drugs is most effective against viruses?

Accepted Answer

Acyclovir

Question 9

Which of the following is a reason why it is more difficult to develop drugs against eukaryotic pathogens than against bacteria?

Accepted Answer

Eukaryotic pathogens share more cellular structures with human cells, reducing selective toxicity.

Question 10

Which of the following best describes the Kirby-Bauer disk diffusion test?

Accepted Answer

A test that evaluates the effectiveness of antibiotics by measuring zones of inhibition around antibiotic disks on an agar plate.

Question 11

A clinical isolate of $$	extit{Staphylococcus aureus} is $$tested using the Kirby-Bauer method. The zone of inhibition for vancomycin is 20 mm. What does this result indicate?

Accepted Answer

The bacterium is susceptible to vancomycin.

Question 12

Which of the following agricultural practices contributes to the development of antimicrobial resistance?

Accepted Answer

Using antibiotics as growth promoters in livestock feed

Question 13

Which of the following clinical practices can accelerate the emergence of antimicrobial resistance?

Accepted Answer

Incomplete courses of antibiotic treatment

Question 14

Which of the following is a multi-step process that can lead to the spread of antimicrobial resistance in a hospital setting?

Accepted Answer

Overuse of broad-spectrum antibiotics, followed by transmission of resistant bacteria between patients

Question 15

Which of the following is NOT a mechanism by which bacteria can acquire resistance genes?

Accepted Answer

Binary fission

Question 16

Which of the following statements about minimum inhibitory concentration (MIC) is correct?

Accepted Answer

MIC is the lowest concentration of an antibiotic that inhibits visible bacterial growth.

Question 17

A patient is infected with a multidrug-resistant strain of $$	extit{Escherichia coli}. $$Which of the following strategies is most likely to be effective?

Accepted Answer

Using combination therapy with two or more antibiotics

Question 18

Which of the following is a real-world consequence of widespread antimicrobial resistance?

Accepted Answer

Increased morbidity and mortality from previously treatable infections

Question 19

Which of the following best explains why combination therapy can reduce the likelihood of resistance development?

Accepted Answer

It targets multiple pathways in the pathogen, making it harder for resistance to develop.

Question 20

Which of the following is a valid equation for calculating the zone of inhibition in the Kirby-Bauer test?

Accepted Answer

$$d = 2r$$

Antimicrobial Drugs and Resistance: Study Notes (Chapter 15)

Study Guide - Practice Questions

Study Guide - Flashcards