Question 1

Which of the following best describes the role of lysozyme in innate immunity?

Accepted Answer

It digests peptidoglycan in bacterial cell walls, leading to cell lysis.

Question 2

A patient presents with a parasitic worm infection. Which leukocyte would you expect to be elevated in their blood count?

Accepted Answer

Eosinophils

Question 3

Which of the following is NOT a function of the normal microbiome in innate immunity?

Accepted Answer

Directly lysing viral particles in the bloodstream

Question 4

Which process is described by the following sequence: chemotaxis, adhesion, ingestion, maturation, killing, elimination?

Accepted Answer

Phagocytosis

Question 5

Which of the following statements about the complement system is TRUE?

Accepted Answer

It can be activated by three pathways: classical, alternative, and lectin.

Question 6

A mutation prevents the production of C3 protein in a patient. Which of the following outcomes is most likely?

Accepted Answer

Impaired opsonization and reduced phagocytosis

Question 7

Which chemical mediator is primarily responsible for vasodilation during acute inflammation?

Accepted Answer

Histamine

Question 8

Which of the following best explains why fever can be beneficial during infection?

Accepted Answer

It enhances the effects of interferons and inhibits the growth of some microbes.

Question 9

Which of the following is a correct pairing of a leukocyte and its primary function?

Accepted Answer

Basophil – release of inflammatory chemicals

Question 10

A patient with a genetic defect in Toll-like receptors (TLRs) would most likely have which of the following problems?

Accepted Answer

Reduced ability to recognize pathogen-associated molecular patterns (PAMPs)

Question 11

Which of the following best describes the role of antimicrobial peptides in innate immunity?

Accepted Answer

They disrupt microbial membranes and interfere with metabolism.

Question 12

Which of the following is a direct result of complement activation?

Accepted Answer

Formation of the membrane attack complex (MAC)

Question 13

Which of the following is a characteristic of acute inflammation but NOT chronic inflammation?

Accepted Answer

Rapid onset and short duration

Question 14

Which of the following best explains why the skin is an effective barrier to pathogens?

Accepted Answer

It consists of multiple layers of tightly packed cells and contains antimicrobial chemicals.

Question 15

Which of the following is a function of interferons in innate immunity?

Accepted Answer

They inhibit the spread of viral infections.

Question 16

A patient with a deficiency in neutrophils would be most susceptible to which of the following?

Accepted Answer

Bacterial infections

Question 17

Which of the following is a correct sequence of events during inflammation?

Accepted Answer

Vasodilation → increased vascular permeability → migration of phagocytes → tissue repair

Question 18

Which of the following best describes the role of sebum in innate immunity?

Accepted Answer

It lowers skin pH, making it inhibitory to many bacteria.

Question 19

Which of the following is a function of natural killer (NK) lymphocytes?

Accepted Answer

They secrete toxins onto the surface of virally infected cells and tumors.

Question 20

Which of the following is a likely outcome if the lacrimal apparatus is nonfunctional?

Accepted Answer

Increased risk of eye infections due to reduced lysozyme activity

Innate Immunity: The Body’s First and Second Lines of Defense

Study Guide - Practice Questions