Verified Questions, Answers & Rationales
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Chamberlain university | 2026/2027 | Newly Released
Section 1: Innate and Adaptive Immunity
Section 2: Immune System Disorders (Hypersensitivity, Autoimmunity,
Immunodeficiency)
Section 3: Hematologic Disorders (Anemias, Coagulopathies)
Q1: Which of the following represents the first line of defense in the innate immune system?
A. B lymphocytes
B. Phagocytes
C. Skin and mucous membranes [CORRECT]
D. T lymphocytes
Correct Answer: C
Rationale: The skin and mucous membranes are physical and chemical barriers that prevent
pathogen entry, constituting the first line of innate defense. B and T cells are part of the adaptive
(third line) system.
Board Pearl: 1st Line = Barriers (Skin/Mucosa); 2nd Line = Innate Internal (Inflammation); 3rd
Line = Adaptive.
, Q2: A child falls and scrapes their knee. Within hours, the area becomes red, warm, and swollen.
Which innate immune cells are the first to arrive at the site of injury to phagocytose pathogens?
A. Eosinophils
B. Neutrophils [CORRECT]
C. Basophils
D. B cells
Correct Answer: B
Rationale: Neutrophils are the primary phagocytes that arrive first at the site of acute
inflammation to ingest and destroy pathogens.
Board Pearl: "First responders" of inflammation = Neutrophils.
Q3: Which immunoglobulin class is primarily found in mucosal secretions such as saliva, tears,
and breast milk?
A. IgG
B. IgM
C. IgA [CORRECT]
D. IgE
Correct Answer: C
Rationale: IgA is the main antibody class found in mucosal secretions, providing localized
immunity by preventing pathogens from entering the body through epithelial surfaces.
Board Pearl: Mucosal guard = IgA.
Q4: During a primary immune response, which antibody is produced first and indicates a recent
infection?
A. IgG
B. IgM [CORRECT]
C. IgA
D. IgE
Correct Answer: B
.