Question 1

Which of the following best describes the main difference between innate and adaptive immunity?

Accepted Answer

Adaptive immunity has immunological memory, while innate immunity does not.

Question 2

A patient receives antibodies against a snake venom through an injection after being bitten. Which type of immunity is this an example of?

Accepted Answer

Artificially acquired passive immunity

Question 3

Which antibody isotype is most abundant in human blood and can cross the placenta to provide immunity to the fetus?

Accepted Answer

IgG

Question 4

What is the primary function of T cytotoxic cells in adaptive immunity?

Accepted Answer

They directly destroy infected, cancerous, or transplanted cells.

Question 5

Which of the following best explains why memory cells are important in adaptive immunity?

Accepted Answer

They allow for a faster and stronger response upon secondary exposure to the same antigen.

Question 6

Which antibody isotype is primarily found in secretions such as saliva, tears, and breast milk, and helps protect mucosal surfaces?

Accepted Answer

IgA

Question 7

A child contracts chickenpox and recovers, developing long-term immunity. Which type of immunity is this?

Accepted Answer

Naturally acquired active immunity

Question 8

Which of the following is a key feature of self-tolerance in adaptive immunity?

Accepted Answer

The elimination of immune cells that react strongly to self-antigens during development.

Question 9

Which antibody isotype is produced first during a primary immune response and is effective at agglutination and complement activation?

Accepted Answer

IgM

Question 10

A vaccine triggers the formation of memory cells and antibodies in a patient. What type of immunity does this represent?

Accepted Answer

Artificially acquired active immunity

Question 11

Which of the following best describes the role of antigen-presenting cells (APCs) in adaptive immunity?

Accepted Answer

They present processed antigens to T cells to initiate an adaptive immune response.

Question 12

Which antibody isotype is most involved in allergic responses and defense against parasitic infections?

Accepted Answer

IgE

Question 13

Which of the following statements about immunological memory is correct?

Accepted Answer

Memory cells allow for a rapid and amplified response upon re-exposure to the same antigen.

Question 14

Which of the following best describes the process of isotype switching in B cells?

Accepted Answer

A B cell changes the class of antibody it produces while maintaining specificity for the same antigen.

Question 15

Which of the following is NOT a function of antibodies?

Accepted Answer

Directly destroying infected host cells

Question 16

Which of the following best explains why IgG is used as an indicator of past infection in serological tests?

Accepted Answer

IgG persists in the blood for a long time after infection and indicates prior exposure.

Question 17

Which of the following best describes the interaction between T helper cells and B cells?

Accepted Answer

T helper cells release cytokines that stimulate B cell activation and antibody production.

Question 18

A patient receives antibodies from their mother through breast milk. Which type of immunity is this?

Accepted Answer

Naturally acquired passive immunity

Question 19

Which of the following best describes the role of epitopes in adaptive immunity?

Accepted Answer

Epitopes are specific regions of an antigen recognized by B and T cells.

Question 20

Which of the following is a correct sequence of events in the adaptive immune response?

Accepted Answer

Antigen presentation → Lymphocyte activation → Lymphocyte proliferation and differentiation → Antigen elimination and memory

Adaptive Immunity: Principles and Mechanisms

Study Guide - Practice Questions