Question 1

Which of the following is a key difference between innate and adaptive immunity?

Accepted Answer

Innate immunity uses pattern recognition receptors, while adaptive immunity uses T cell receptors and antibodies.

Question 2

Which organ is NOT considered a primary lymphoid organ?

Accepted Answer

Spleen

Question 3

What is the main function of B lymphocytes in adaptive immunity?

Accepted Answer

Secretion of antibodies

Question 4

Which of the following statements about antigens is TRUE?

Accepted Answer

Antigens are recognized by three-dimensional regions called epitopes.

Question 5

Which class of MHC proteins is present on all nucleated cells except red blood cells?

Accepted Answer

MHC class I

Question 6

A patient receives a tissue graft. Which molecules are most important in determining compatibility?

Accepted Answer

Major histocompatibility complex (MHC) antigens

Question 7

Which of the following is a function of antibodies?

Accepted Answer

Activation of complement and inflammation

Question 8

Which antibody class is most common and longest-lasting in the body?

Accepted Answer

IgG

Question 9

What is the role of regulatory T lymphocytes in adaptive immunity?

Accepted Answer

Repress adaptive immune responses

Question 10

Which cytokine is responsible for the cloning of cytotoxic T cells?

Accepted Answer

Interleukin 2 (IL-2)

Question 11

During clonal deletion, what happens to self-reactive T cells?

Accepted Answer

They undergo apoptosis

Question 12

Which pathway is used by cytotoxic T cells to kill infected cells?

Accepted Answer

Perforin-granzyme pathway

Question 13

What is the main difference between primary and secondary antibody immune responses?

Accepted Answer

Secondary response is faster and produces more antibodies than primary response.

Question 14

Which of the following is an example of naturally acquired passive immunity?

Accepted Answer

Antibodies transferred from mother to offspring via placenta or breast milk

Question 15

Why is passive immunity effective more quickly than active immunity?

Accepted Answer

Passive immunity provides pre-formed antibodies, bypassing the need for immune system activation.

Question 16

Which enzyme is responsible for generating antibody diversity in B cells?

Accepted Answer

RAG enzyme

Question 17

A patient with an autoimmune disease likely has a breakdown in which attribute of adaptive immunity?

Accepted Answer

Unresponsiveness to self

Question 18

Which of the following is TRUE about memory B cells?

Accepted Answer

They persist in lymphoid tissue and initiate antibody production upon re-exposure to antigen.

Question 19

Which immune response is primarily responsible for defending against intracellular pathogens such as viruses?

Accepted Answer

Cell-mediated immune response

Question 20

Which cytokine increases phagocytosis by macrophages?

Accepted Answer

Gamma interferon (IFN-γ)

Adaptive Immunity: Mechanisms and Components

Study Guide - Practice Questions