NR507-NP MIDTERM EXAM QUESTIONS
WITH 100% CORRECT ANSWERS WITH
RATIONALES | VERIFIED | LATEST
UPDATE
1. Which of the following are considered the "first responders" of the innate
immune system?
A) Macrophages
B) B-lymphocytes
C) Neutrophils
D) Natural killer cells
Answer: C) Neutrophils
Rationale: Neutrophils are the first responders of the innate immune system and
appear first in any immune response. They are the most abundant type of white
blood cells and rapidly migrate to sites of infection or inflammation.
2. Hives (urticaria) are an example of which type of hypersensitivity reaction?
A) Type 1 Hypersensitivity
B) Type 2 Hypersensitivity
C) Type 3 Hypersensitivity
D) Type 4 Hypersensitivity
Answer: A) Type 1 Hypersensitivity
Rationale: Hives are a Type 1 hypersensitivity reaction mediated by IgE antibodies
and mast cells. When an allergen binds to IgE on mast cells, degranulation occurs,
1
,releasing histamine and other inflammatory mediators that cause localized wheal-
and-flare responses.
3. Anaphylaxis is classified as which type of hypersensitivity reaction?
A) Type 1
B) Type 2
C) Type 3
D) Type 4
Answer: A) Type 1
Rationale: Anaphylaxis is a Type 1 hypersensitivity reaction mediated by IgE and
mast cells. In highly sensitized individuals, exposure to the antigen can trigger
widespread mast cell degranulation, leading to systemic vasodilation,
bronchoconstriction, and potentially life-threatening cardiovascular collapse.
4. Allergic contact dermatitis is an example of which type of hypersensitivity
reaction?
A) Type 1
B) Type 2
C) Type 3
D) Type 4
Answer: D) Type 4
Rationale: Allergic contact dermatitis is a Type 4 hypersensitivity reaction
mediated by T-cells, not antibodies. When the individual comes in contact with the
allergen (e.g., poison ivy), sensitized T-cells activate the inflammatory process,
causing the delayed reaction that appears 24-72 hours after exposure.
5. Type 2 (Cytotoxic) hypersensitivity reactions are mediated by which
immunoglobulins?
2
,A) IgA or IgE
B) IgM or IgA
C) IgG or IgM
D) IgE or IgG
Answer: C) IgG or IgM
Rationale: Type 2 hypersensitivity reactions are mediated by IgG or IgM
antibodies directed against antigens on cell surfaces. These antibodies can activate
complement, leading to cell lysis, or opsonize cells for destruction by macrophages
and other phagocytes.
6. During the sensitization phase of a Type 1 hypersensitivity reaction, IgE
molecules bind to which cells?
A) Neutrophils and macrophages
B) Mast cells, basophils, and eosinophils
C) T-lymphocytes and B-lymphocytes
D) Natural killer cells and dendritic cells
Answer: B) Mast cells, basophils, and eosinophils
Rationale: During sensitization, IgE molecules bind to Fc receptors on mast cells,
basophils, and eosinophils. On subsequent exposure to the allergen, these
sensitized cells degranulate, releasing inflammatory mediators such as histamine,
leukotrienes, and prostaglandins.
7. Which of the following is a classic example of a Type 2 hypersensitivity
reaction?
A) Allergic asthma
B) Serum sickness
C) Hemolytic anemia
D) Contact dermatitis
3
, Answer: C) Hemolytic anemia
Rationale: Hemolytic anemia is a classic Type 2 hypersensitivity reaction where
IgG or IgM antibodies target red blood cell antigens, leading to complement-
mediated lysis or phagocytic destruction.
8. A patient with chronic hypertension presents with an enlarged heart. This
increase in cardiac muscle mass is primarily due to which cellular adaptation?
A) Hyperplasia
B) Hypertrophy
C) Atrophy
D) Metaplasia
Answer: B) Hypertrophy
Rationale: Cardiac muscle cells are terminally differentiated and cannot divide.
They respond to increased workload (afterload) from chronic hypertension by
increasing in size (hypertrophy) rather than number (hyperplasia).
9. A patient with chronic GERD develops Barrett esophagus, where normal
squamous epithelium is replaced by columnar epithelium. This process is known
as:
A) Dysplasia
B) Metaplasia
C) Anaplasia
D) Hyperplasia
Answer: B) Metaplasia
Rationale: Metaplasia is the reversible replacement of one differentiated cell type
with another, typically in response to chronic irritation. While initially protective,
Barrett esophagus increases the risk for dysplasia and esophageal adenocarcinoma.
4
WITH 100% CORRECT ANSWERS WITH
RATIONALES | VERIFIED | LATEST
UPDATE
1. Which of the following are considered the "first responders" of the innate
immune system?
A) Macrophages
B) B-lymphocytes
C) Neutrophils
D) Natural killer cells
Answer: C) Neutrophils
Rationale: Neutrophils are the first responders of the innate immune system and
appear first in any immune response. They are the most abundant type of white
blood cells and rapidly migrate to sites of infection or inflammation.
2. Hives (urticaria) are an example of which type of hypersensitivity reaction?
A) Type 1 Hypersensitivity
B) Type 2 Hypersensitivity
C) Type 3 Hypersensitivity
D) Type 4 Hypersensitivity
Answer: A) Type 1 Hypersensitivity
Rationale: Hives are a Type 1 hypersensitivity reaction mediated by IgE antibodies
and mast cells. When an allergen binds to IgE on mast cells, degranulation occurs,
1
,releasing histamine and other inflammatory mediators that cause localized wheal-
and-flare responses.
3. Anaphylaxis is classified as which type of hypersensitivity reaction?
A) Type 1
B) Type 2
C) Type 3
D) Type 4
Answer: A) Type 1
Rationale: Anaphylaxis is a Type 1 hypersensitivity reaction mediated by IgE and
mast cells. In highly sensitized individuals, exposure to the antigen can trigger
widespread mast cell degranulation, leading to systemic vasodilation,
bronchoconstriction, and potentially life-threatening cardiovascular collapse.
4. Allergic contact dermatitis is an example of which type of hypersensitivity
reaction?
A) Type 1
B) Type 2
C) Type 3
D) Type 4
Answer: D) Type 4
Rationale: Allergic contact dermatitis is a Type 4 hypersensitivity reaction
mediated by T-cells, not antibodies. When the individual comes in contact with the
allergen (e.g., poison ivy), sensitized T-cells activate the inflammatory process,
causing the delayed reaction that appears 24-72 hours after exposure.
5. Type 2 (Cytotoxic) hypersensitivity reactions are mediated by which
immunoglobulins?
2
,A) IgA or IgE
B) IgM or IgA
C) IgG or IgM
D) IgE or IgG
Answer: C) IgG or IgM
Rationale: Type 2 hypersensitivity reactions are mediated by IgG or IgM
antibodies directed against antigens on cell surfaces. These antibodies can activate
complement, leading to cell lysis, or opsonize cells for destruction by macrophages
and other phagocytes.
6. During the sensitization phase of a Type 1 hypersensitivity reaction, IgE
molecules bind to which cells?
A) Neutrophils and macrophages
B) Mast cells, basophils, and eosinophils
C) T-lymphocytes and B-lymphocytes
D) Natural killer cells and dendritic cells
Answer: B) Mast cells, basophils, and eosinophils
Rationale: During sensitization, IgE molecules bind to Fc receptors on mast cells,
basophils, and eosinophils. On subsequent exposure to the allergen, these
sensitized cells degranulate, releasing inflammatory mediators such as histamine,
leukotrienes, and prostaglandins.
7. Which of the following is a classic example of a Type 2 hypersensitivity
reaction?
A) Allergic asthma
B) Serum sickness
C) Hemolytic anemia
D) Contact dermatitis
3
, Answer: C) Hemolytic anemia
Rationale: Hemolytic anemia is a classic Type 2 hypersensitivity reaction where
IgG or IgM antibodies target red blood cell antigens, leading to complement-
mediated lysis or phagocytic destruction.
8. A patient with chronic hypertension presents with an enlarged heart. This
increase in cardiac muscle mass is primarily due to which cellular adaptation?
A) Hyperplasia
B) Hypertrophy
C) Atrophy
D) Metaplasia
Answer: B) Hypertrophy
Rationale: Cardiac muscle cells are terminally differentiated and cannot divide.
They respond to increased workload (afterload) from chronic hypertension by
increasing in size (hypertrophy) rather than number (hyperplasia).
9. A patient with chronic GERD develops Barrett esophagus, where normal
squamous epithelium is replaced by columnar epithelium. This process is known
as:
A) Dysplasia
B) Metaplasia
C) Anaplasia
D) Hyperplasia
Answer: B) Metaplasia
Rationale: Metaplasia is the reversible replacement of one differentiated cell type
with another, typically in response to chronic irritation. While initially protective,
Barrett esophagus increases the risk for dysplasia and esophageal adenocarcinoma.
4
