Question 1

Which of the following best describes the primary function of interferons (IFN-α and IFN-β) as shown in the provided diagram?

Accepted Answer

They bind to healthy neighboring cells and stimulate the synthesis of enzymes that interfere with viral replication.

Question 2

In the context of the complement system, what is the role of opsonization as depicted in the images?

Accepted Answer

It marks pathogens for enhanced phagocytosis by binding complement proteins to their surface.

Question 3

Which event is most directly responsible for the increased redness and heat observed during inflammation?

Accepted Answer

Vasodilation of arterioles and increased blood flow to the affected area.

Question 4

A patient with a genetic deficiency in the formation of membrane attack complexes (MAC) would most likely have difficulty with which immune process?

Accepted Answer

Cytolysis of pathogens by complement proteins.

Question 5

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

Accepted Answer

It inhibits microbial reproduction and enhances the activity of immune cells.

Question 6

Which cell type is responsible for releasing cytotoxic chemicals such as perforin and granzymes to induce apoptosis in infected cells?

Accepted Answer

Natural Killer (NK) cells

Question 7

What is the primary function of the Fc region of an antibody?

Accepted Answer

It determines the biological function of the antibody and binds to immune cell receptors.

Question 8

Which antibody class is most associated with allergic reactions and activation of mast cells and basophils?

Accepted Answer

IgE

Question 9

A child is exposed to a new virus. Which process allows dendritic cells to initiate an adaptive immune response?

Accepted Answer

Phagocytosis of the virus and presentation of viral antigens on MHC molecules.

Question 10

Which of the following best describes the process of chemotaxis during inflammation?

Accepted Answer

Leukocytes are attracted to the site of infection by increasing concentrations of chemicals released by damaged cells and pathogens.

Question 11

Which of the following is a risk associated with a fever above 106°F (41°C)?

Accepted Answer

Brain damage

Question 12

Which of the following is true regarding the difference between MHC class I and MHC class II molecules?

Accepted Answer

MHC class I displays endogenous antigens, while MHC class II displays exogenous antigens.

Question 13

Which antibody action involves cross-linking antigens on foreign cells, causing them to clump together?

Accepted Answer

Agglutination

Question 14

A patient with a deficiency in IgA would most likely experience which of the following?

Accepted Answer

Increased susceptibility to infections at mucosal surfaces.

Question 15

Which of the following best describes the process of diapedesis?

Accepted Answer

Leukocytes squeeze between endothelial cells of blood vessels to enter tissues.

Question 16

Which of the following is a function of kinins released during inflammation?

Accepted Answer

Stimulate pain receptors and increase production of CAMs

Question 17

Which of the following is a characteristic of haptens?

Accepted Answer

They are small molecules that can trigger an immune response only after binding to a body protein.

Question 18

Which of the following is NOT a benefit of inflammation?

Accepted Answer

Suppression of adaptive immune cells

Question 19

Which of the following best describes the role of IgM antibodies?

Accepted Answer

They are the first antibodies produced during an initial immune response and are effective at agglutination and complement binding.

The Immune System: Innate and Adaptive Defenses

Study Guide - Practice Questions