Question 1

Which of the following best describes the process depicted in the first image, where a cell engulfs and digests a bacterium?

Accepted Answer

Phagocytosis

Question 2

During phagocytosis, which cellular structure fuses with the phagosome to form the phagolysosome, enabling digestion of the ingested microbe?

Accepted Answer

Lysosome

Question 3

Which of the following is NOT a sign of inflammation?

Accepted Answer

Fever

Question 4

A patient receives antibodies from their mother through breast milk. What type of immunity is this?

Accepted Answer

Naturally acquired passive immunity

Question 5

Which of the following best explains why penicillin is selectively toxic to bacteria but not to human cells?

Accepted Answer

Penicillin inhibits peptidoglycan synthesis, which is unique to bacterial cell walls.

Question 6

Which of the following is a mechanism by which bacteria can develop resistance to antibiotics?

Accepted Answer

Producing enzymes that inactivate the antibiotic

Question 7

A vaccine made from a weakened but live pathogen is called:

Accepted Answer

Live attenuated vaccine

Question 8

Which of the following best describes the role of siderophores in bacterial pathogenicity?

Accepted Answer

They bind iron tightly, allowing bacteria to acquire iron from the host.

Question 9

In the adaptive immune response, which cell type is primarily responsible for producing antibodies?

Accepted Answer

B cells

Question 10

Which of the following statements about exotoxins is TRUE?

Accepted Answer

Exotoxins are proteins secreted by bacteria and can be inactivated by antitoxins.

Question 11

Which of the following best describes the function of interferons?

Accepted Answer

They are cytokines that interfere with viral multiplication in host cells.

Question 12

A patient is given a vaccine containing inactivated toxins. What type of vaccine is this?

Accepted Answer

Toxoid vaccine

Question 13

Which of the following is a correct statement about the complement system?

Accepted Answer

It is a cascade of serum proteins that can result in cytolysis, opsonization, and inflammation.

Question 14

Which of the following is a function of regulatory T cells?

Accepted Answer

They regulate the immune response to prevent overactivation.

Question 15

Which of the following best explains why using antibiotics for viral infections can contribute to antibiotic resistance?

Accepted Answer

Antibiotics select for resistant bacteria even when not needed, increasing the prevalence of resistance genes.

Question 16

Which of the following is a plausible outcome if a patient fails to complete their prescribed antibiotic regimen?

Accepted Answer

Resistant bacteria may survive and multiply, leading to a harder-to-treat infection.

Question 17

Which of the following is a key difference between humoral and cellular immunity, as shown in the second image?

Accepted Answer

Humoral immunity involves antibodies produced by B cells, while cellular immunity involves T cells targeting infected cells.

Question 18

Which of the following best describes the role of antigen-presenting cells (APCs) in the immune response?

Accepted Answer

They display antigen fragments on their surface to activate T cells.

Question 19

A patient is infected with a bacterium that produces hyaluronidase. What is the most likely effect of this enzyme?

Accepted Answer

It digests hyaluronic acid, allowing the bacterium to spread through connective tissue.

Question 20

Which of the following best describes the concept of selective toxicity in antimicrobial therapy?

Accepted Answer

The drug targets microbial structures or functions not found in the host.

Principles of Infectious Disease, Immunity, and Antimicrobial Drugs: Study Notes

Study Guide - Practice Questions