Question 1

Which of the following is NOT considered an innate body defense mechanism?

Accepted Answer

Antibodies

Question 2

What is the primary function of interferons in the immune response?

Accepted Answer

Prevent viral replication

Question 3

Which cell type is responsible for presenting antigens to T cells and activating them?

Accepted Answer

Macrophages

Question 4

A patient receives an injection of gamma globulin after exposure to hepatitis. What type of immunity is this?

Accepted Answer

Artificially acquired passive immunity

Question 5

Which of the following best describes the role of cytotoxic T cells (CD8+)?

Accepted Answer

They directly kill infected or cancerous cells using perforin.

Question 6

Which process ensures that T cells do NOT react against the body’s own cells?

Accepted Answer

Negative selection

Question 7

A vaccine works by stimulating which type of immunity?

Accepted Answer

Artificially acquired active immunity

Question 8

Which immunoglobulin class is most abundant in plasma and is responsible for secondary immune responses?

Accepted Answer

IgG

Question 9

What is the main function of helper T cells (CD4+)?

Accepted Answer

Stimulate proliferation and activity of other lymphocytes

Question 10

Which of the following best describes the concept of immunological memory?

Accepted Answer

The ability of the immune system to respond more rapidly and effectively to pathogens that have been encountered previously

Question 11

Which of the following is TRUE regarding the major histocompatibility complex (MHC)?

Accepted Answer

MHC proteins present antigens to T cells

Question 12

A person is exposed to influenza virus for the first time. Which defense is activated first?

Accepted Answer

Surface barriers such as skin and mucous membranes

Question 13

Which of the following is a function of antibodies?

Accepted Answer

Tag antigens for destruction by other immune cells

Question 14

Which of the following best explains why only a small percentage of T cells survive maturation in the thymus?

Accepted Answer

Most T cells fail to recognize self-MHC or react too strongly to self-antigens

Question 15

Which of the following is a key difference between B cells and T cells?

Accepted Answer

B cells produce antibodies, while T cells mediate cellular immunity

Question 16

Which of the following best describes the process of clonal selection?

Accepted Answer

The proliferation of lymphocytes that have bound to a specific antigen

Question 17

Which of the following is a characteristic of the secondary immune response compared to the primary immune response?

Accepted Answer

It is faster and produces more antibodies

Question 18

Which immunoglobulin class is primarily found in secretions such as saliva and breast milk?

Accepted Answer

IgA

Question 19

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

Accepted Answer

Suppress the immune response to prevent overactivity

Question 20

Which of the following best describes the role of memory cells in the immune system?

Accepted Answer

They provide a rapid and robust response upon re-exposure to the same antigen

Immune System: Innate and Adaptive Defenses

Study Guide - Practice Questions