Question 1

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

Accepted Answer

They process and present antigens to T cells to initiate an immune response.

Question 2

Which agranulocyte acts as an antigen presenting cell (APC)?

Accepted Answer

Monocyte

Question 3

Which of the following statements is TRUE regarding the activation of T and B cells?

Accepted Answer

Only T cells require antigen presentation for activation; B cells can be activated by direct antigen binding.

Question 4

What is the significance of penicillin acting as a hapten?

Accepted Answer

It can bind to host proteins, forming a complex that is recognized as foreign, potentially triggering an allergic response.

Question 5

Which of the following correctly lists antigens from most immunogenic to least immunogenic?

Accepted Answer

Proteins, polysaccharides, lipids, haptens

Question 6

A patient is diagnosed with HIV. Which T cell population is primarily destroyed by the virus, leading to immunodeficiency?

Accepted Answer

CD4+ helper T cells

Question 7

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

Accepted Answer

The process by which a single B or T cell divides and differentiates after activation to produce a population of identical cells.

Question 8

Which of the following is a function of T helper (Th) cells?

Accepted Answer

Bridging the cellular and humoral branches of adaptive immunity by activating B cells and cytotoxic T cells

Question 9

Which of the following best explains the importance of gene shuffling in the immune system?

Accepted Answer

It increases the diversity of antigen receptors on B and T cells, enabling recognition of a vast array of antigens.

Question 10

Which of the following best describes self-tolerance in the immune system?

Accepted Answer

The process by which immune cells are screened to avoid attacking the body's own tissues.

Question 11

Which type of cells express both MHC I and MHC II proteins on their surface?

Accepted Answer

Antigen presenting cells (APCs) such as dendritic cells, macrophages, and B cells

Question 12

Which class of MHC proteins presents intracellular antigens?

Accepted Answer

MHC I

Question 13

A patient receives a bone marrow transplant and develops graft-versus-host disease (GVHD). What is the underlying cause of this condition?

Accepted Answer

The donor immune cells attack the recipient's tissues, recognizing them as foreign.

Question 14

Which two molecules are released by cytotoxic T cells after binding to an MHC I–antigen complex, and what are their functions?

Accepted Answer

Perforin and granzymes; perforin forms pores in the target cell membrane and granzymes induce apoptosis.

Question 15

Which antibody isotype is the most abundant in blood and is capable of crossing the placenta?

Accepted Answer

IgG

Question 16

A newborn is found to have high levels of IgG specific to a pathogen, but no detectable IgM. What can you conclude?

Accepted Answer

The IgG was transferred from the mother across the placenta, indicating maternal immunity.

Question 17

Which antibody isotype is primarily produced during the early stages of a primary immune response?

Accepted Answer

IgM

Question 18

Which antibody isotype is found in mother's milk in a dimeric form and provides mucosal immunity to infants?

Accepted Answer

IgA

Question 19

A patient receives antivenom after a snake bite. Which type of immunity does this represent?

Accepted Answer

Artificially acquired passive immunity

Question 20

Which of the following best defines antibody titer?

Accepted Answer

The concentration of a specific antibody in the blood, often determined by serial dilution.

Adaptive Immunity Study Guide – Step-by-Step Guidance

Guida di studio - Domande di pratica