Question 1

Which of the following best describes the process of opsonization in innate immunity?

Accepted Answer

The coating of pathogens with molecules that enhance their recognition and ingestion by phagocytes.

Question 2

A patient presents with a fever of 39°C. Which of the following statements about fever is correct?

Accepted Answer

Fever is generated by pyrogens that act on the hypothalamus to raise the body's set point temperature.

Question 3

Which of the following is NOT a function of the complement system?

Accepted Answer

Directly producing antibodies to neutralize pathogens.

Question 4

Which immune cells are classified as professional phagocytes?

Accepted Answer

Neutrophils, macrophages, and dendritic cells

Question 5

A laboratory test distinguishes between serum and plasma. Which of the following correctly differentiates them?

Accepted Answer

Serum is plasma without clotting factors.

Question 6

Which of the following best explains why normal microbiota are important for immune defense?

Accepted Answer

They compete with pathogens for nutrients and space, limiting pathogen colonization.

Question 7

Which of the following statements about Major Histocompatibility Complex (MHC) molecules is correct?

Accepted Answer

MHC I is expressed on all nucleated cells, while MHC II is expressed mainly on antigen-presenting cells.

Question 8

A patient receives a kidney transplant and experiences rejection. Which immunological principle explains this phenomenon?

Accepted Answer

Differences in MHC molecules between donor and recipient trigger an immune response.

Question 9

Which of the following best describes the difference between T cell receptors (TCRs) and B cell receptors (BCRs)?

Accepted Answer

TCRs recognize antigens only when presented by MHC molecules, while BCRs can bind free antigens.

Question 10

Which antibody class is most abundant in serum and is capable of crossing the placenta to provide passive immunity to the fetus?

Accepted Answer

IgG

Question 11

A patient is exposed to a pathogen for the second time. Which of the following best describes the immunological memory response?

Accepted Answer

The secondary response is faster and produces higher antibody titers than the primary response.

Question 12

Which of the following is a correct statement about isotype switching in B cells?

Accepted Answer

Isotype switching allows a B cell to produce different classes of antibodies with the same antigen specificity.

Question 13

Which of the following best describes the principle of herd immunity?

Accepted Answer

When a high percentage of a population is immune, the spread of infectious disease is limited, protecting those who are not immune.

Question 14

Which of the following laboratory diagnostic methods is most appropriate for detecting the presence of viral RNA in a patient sample?

Accepted Answer

Reverse transcription PCR (RT-PCR)

Question 15

A new vaccine formulation includes an adjuvant. What is the primary purpose of an adjuvant in a vaccine?

Accepted Answer

To enhance the immune response to the antigen.

Question 16

Which of the following best describes the function of lysozyme in innate immunity?

Accepted Answer

It breaks down the peptidoglycan layer of bacterial cell walls.

Question 17

A patient is tested for tuberculosis using an interferon gamma release assay (IGRA). What is the principle behind this test?

Accepted Answer

It measures the release of interferon gamma by T cells in response to Mycobacterium tuberculosis antigens.

Question 18

Which of the following is a correct statement about the four cardinal signs of inflammation?

Accepted Answer

They are redness, heat, swelling, and pain, resulting from increased blood flow and vascular permeability.

Question 19

Which of the following best explains why an immune response to infection often causes fatigue?

Accepted Answer

Cytokines released during the immune response affect the brain and energy metabolism.

Question 20

A patient is given a live attenuated vaccine. Which of the following statements is correct regarding this type of vaccine?

Accepted Answer

It contains a weakened form of the pathogen that can replicate and induce a strong, long-lasting immune response.

Innate and Adaptive Immunity, Vaccines, and Laboratory Diagnostics: Study Notes

Study Guide - Practice Questions