$$ \text{Antibody Titer} = \text{IgM}_{\text{primary}} + \text{IgG}_{\text{secondary}} $$

$$ \text{Number of B cells after expansion} = \text{Initial B cells} \times 2$$^{n}$$ $$

Question 1

Which of the following best describes the dual nature of adaptive immunity?

Accepted Answer

It involves both B cells (humoral immunity) and T cells (cell-mediated immunity), each targeting pathogens in different ways.

Question 2

What is the primary function of MHC class I molecules?

Accepted Answer

To display intracellular antigens for recognition by cytotoxic T cells.

Question 3

A patient receives antibodies from another individual to treat a snake bite. Which type of immunity is this?

Accepted Answer

Artificially acquired passive immunity

Question 4

Which process allows lymphocytes to generate over a billion unique antigen receptors despite having only about 30,000 to 40,000 genes?

Accepted Answer

Somatic recombination

Question 5

What is the consequence of antigen-antibody binding known as opsonization?

Accepted Answer

Antibodies cover the antigen, enhancing ingestion and lysis by phagocytic cells.

Question 6

Which equation best represents the antibody titer in serum over time after primary and secondary exposure to an antigen?

Accepted Answer

$$ 	ext{Antibody Titer} = 	ext{IgM}_{	ext{primary}} + 	ext{IgG}_{	ext{secondary}} $$

Question 7

Which cell type is responsible for directly killing virus-infected cells by recognizing non-self antigens presented on MHC class I molecules?

Accepted Answer

Cytotoxic T cells (CD8+)

Question 8

What is the role of memory B cells in the adaptive immune response?

Accepted Answer

They proliferate and differentiate into plasma cells upon subsequent exposure to the same antigen.

Question 9

Which of the following is a real-world example of neutralization by antibodies?

Accepted Answer

Antibodies binding to viral surface proteins, preventing the virus from entering host cells.

Question 10

Which equation describes the clonal expansion of B cells after activation?

Accepted Answer

$$ 	ext{Number of B cells after expansion} = 	ext{Initial B cells} 	imes 2$$^{n}$$ $$

Question 11

Which of the following best explains why cancer cells may be susceptible to Natural Killer (NK) cells?

Accepted Answer

Cancer cells lose expression of MHC class I molecules, making them targets for NK cells.

Question 12

Which of the following is NOT a function of professional antigen-presenting cells (APCs)?

Accepted Answer

Directly killing virus-infected cells

Question 13

During T cell selection in the thymus, what happens to T cells that react vigorously with self peptides?

Accepted Answer

They undergo apoptosis to prevent autoimmunity.

Question 14

Which of the following is a consequence of complement activation by antibodies?

Accepted Answer

Cell lysis and inflammation

Question 15

Which equation best represents the probability of a lymphocyte recognizing a specific antigen, given random receptor diversity?

Accepted Answer

$$ P = \frac{	ext{Number of functional receptors}}{	ext{Total possible receptors}} $$

Question 16

Which of the following best describes the function of lymph nodes?

Accepted Answer

They filter lymph and bring antigens to a single location to be screened by T and B cells.

Question 17

A patient is exposed to a weakened pathogen through vaccination and produces antibodies in response. What type of immunity is this?

Accepted Answer

Artificially acquired active immunity

Question 18

Which of the following is a key difference between T-dependent and T-independent activation of B cells?

Accepted Answer

T-dependent activation requires antigen presentation with MHC and cytokine signaling from helper T cells.

Question 19

Which equation best represents the rate of antibody production during the secondary immune response?

Accepted Answer

$$ 	ext{Rate}_{	ext{secondary}} = 	ext{Rate}_{	ext{primary}} 	imes k $$

Chapter 17: Adaptive (Specific) Immunity – The Immune Response

Study Guide - Practice Questions