Question 1

Which of the following best describes the role of histamine during the inflammatory response?

Accepted Answer

Histamine increases the permeability of blood vessels, allowing defensive substances to enter the affected tissue.

Question 2

A patient presents with a bacterial infection. Which step of inflammation is responsible for the migration of neutrophils to the infection site?

Accepted Answer

Phagocyte migration and phagocytosis

Question 3

Which of the following is a correct sequence of events in the classical pathway of complement activation?

Accepted Answer

Antibody binds antigen → C1 activation → C2 and C4 activation → C3 activation

Question 4

Which of the following outcomes is NOT a result of complement activation?

Accepted Answer

Direct inhibition of viral replication by degrading viral RNA

Question 5

A patient with a genetic deficiency in C3 complement protein would most likely have problems with which of the following?

Accepted Answer

Forming membrane attack complexes (MAC) and opsonizing pathogens

Question 6

Which of the following statements about the alternative pathway of complement activation is TRUE?

Accepted Answer

It is initiated by the binding of C3 to microbial surfaces and factors B, D, and P.

Question 7

Which of the following best explains why Gram-negative bacteria are more susceptible to cytolysis by the complement system?

Accepted Answer

Their outer membrane allows easier insertion of the membrane attack complex (MAC), leading to cell lysis.

Question 8

Which of the following is a function of interferon-gamma (IFN-γ)?

Accepted Answer

Causes neutrophils and macrophages to produce nitric oxide, inhibiting ATP production in bacteria and tumor cells

Question 9

A patient with a fever is experiencing shivering and vasoconstriction. What is the physiological explanation for these symptoms?

Accepted Answer

Cytokines have caused the hypothalamus to release prostaglandins, raising the set point and triggering heat-generating mechanisms.

Question 10

Which of the following iron-binding proteins is found in milk, saliva, and mucus?

Accepted Answer

Lactoferrin

Question 11

A bacterial pathogen releases hemolysin to destroy red blood cells. What is the primary advantage of this strategy for the pathogen?

Accepted Answer

To release iron from hemoglobin, which the bacteria can use for growth

Question 12

Which of the following is NOT a mechanism of action for antimicrobial peptides (AMPs)?

Accepted Answer

Stimulating the production of siderophores

Question 13

Which of the following best describes the difference between stroma and parenchyma in tissue repair?

Accepted Answer

Stroma is the supporting connective tissue, while parenchyma is the functional part of the tissue.

Question 14

Which of the following is a unique feature of antimicrobial peptides (AMPs) compared to antibiotics?

Accepted Answer

AMPs are produced by the host and microbes do not appear to develop resistance to them.

Question 15

Which of the following best explains the process of opsonization?

Accepted Answer

Complement proteins coat a microbe, making it easier for phagocytes to recognize and ingest it.

Question 16

A patient is unable to produce kinins and leukotrienes. Which aspect of the inflammatory response would be most affected?

Accepted Answer

Chemotaxis of phagocytes to the site of infection

Question 17

Which of the following is the correct LaTeX representation for the splitting of complement protein C3 into its active forms?

Accepted Answer

$$C3 \rightarrow C3a + C3b$$

Question 18

Which of the following best describes the role of prostaglandins in fever?

Accepted Answer

They reset the hypothalamic thermostat to a higher temperature in response to cytokines.

Question 19

Which of the following is a real-world example of the importance of iron-binding proteins in host defense?

Accepted Answer

A patient with iron overload is more susceptible to bacterial infections because excess iron is available for bacterial growth.

Innate Immunity: Nonspecific Defenses of the Host – Inflammation, Fever, and Antimicrobial Substances

Study Guide - Practice Questions