Question 1

Which of the following best describes the process of opsonization in the immune response?

Accepted Answer

It is the coating of pathogens with molecules such as antibodies or complement proteins to enhance phagocytosis.

Question 2

A patient presents with a high eosinophil count (eosinophilia). Which of the following is the most likely cause?

Accepted Answer

A parasitic worm infection

Question 3

Which of the following white blood cells is classified as an agranulocyte and is primarily responsible for differentiating into macrophages in tissues?

Accepted Answer

Monocyte

Question 4

During the classical pathway of the complement cascade, which molecule initiates the cascade by binding to antigen-antibody complexes?

Accepted Answer

C1

Question 5

Which of the following best explains the difference between exogenous and endogenous antigens in terms of MHC presentation?

Accepted Answer

Exogenous antigens are presented on MHC II, while endogenous antigens are presented on MHC I.

Question 6

A patient receives an injection of pre-formed antibodies after exposure to rabies. Which type of immunity is this an example of?

Accepted Answer

Artificially acquired passive immunity

Question 7

Which immunoglobulin is the first to appear in significant quantities during a primary immune response?

Accepted Answer

IgM

Question 8

Which of the following best describes the function of dendritic cells in the immune system?

Accepted Answer

They present antigens to T cells to initiate adaptive immune responses.

Question 9

A 5-year-old child receives a live, attenuated vaccine. Which of the following is a potential advantage of this type of vaccine?

Accepted Answer

It stimulates a strong, long-lasting immune response similar to natural infection.

Question 10

Which of the following best describes the mechanism of a Type I hypersensitivity reaction?

Accepted Answer

IgE-mediated degranulation of mast cells and basophils, releasing histamine

Question 11

A patient with HIV is found to have a declining CD4+ T cell count. Which enzyme, encoded by HIV, is responsible for converting viral RNA into DNA?

Accepted Answer

Reverse transcriptase

Question 12

Which of the following best explains why clonal deletion is important in the development of self-tolerance?

Accepted Answer

It removes lymphocytes that react strongly to self-antigens, preventing autoimmunity.

Question 13

Which of the following is a correct sequence of events in phagocytosis?

Accepted Answer

Chemotaxis → Adherence → Ingestion → Digestion → Elimination

Question 14

A patient develops hemolytic disease of the newborn. Which of the following best explains the immunological mechanism behind this condition?

Accepted Answer

Maternal IgG antibodies against fetal red blood cell antigens cross the placenta and mediate cell destruction.

Question 15

Which of the following best describes the function of Natural Killer (NK) cells?

Accepted Answer

They kill virus-infected and tumor cells by releasing perforin and granzymes.

Question 16

Which of the following is a key difference between primary and secondary immune responses?

Accepted Answer

The secondary response involves memory cells and produces more IgG more rapidly.

Question 17

Which of the following best describes the role of interleukins in the immune system?

Accepted Answer

They are signaling molecules that mediate communication between leukocytes.

Question 18

A patient is given a tuberculin skin test. A positive result may indicate which of the following?

Accepted Answer

The patient has been exposed to Mycobacterium tuberculosis or has received the BCG vaccine.

Question 19

Which of the following best describes the function of the enzyme integrase in the HIV life cycle?

Accepted Answer

It incorporates viral DNA into the host cell genome.

Question 20

Which of the following is a characteristic of an inactivated (killed) vaccine?

Accepted Answer

It often requires booster doses to maintain immunity.

Comprehensive Microbiology Exam Review Guidance (Chapters 15–18)

Study Guide - Practice Questions

Study Guide - Flashcards