NUR 555 Quiz 2: Immunology and Inflammation |
Questions and Correct Answers plus Rationale | New
Update 2026-2027 | SNHU
Question 1: Which chemical mediator derived from mast cells retracts
endothelial cells to increase vascular permeability and to cause leukocyte
adhesion to endothelial cells?
A. Bradykinin
B. Platelet-activating factor
C. Prostaglandin E
D. Chemokines
Correct Answer: B. Platelet-activating factor
Rationale: The biologic activity of platelet-activating factor (PAF) is virtually
identical to that of leukotrienes. PAF causes endothelial cell retraction to increase
vascular permeability, leukocyte adhesion to endothelium, and platelet activation.
Option A (Bradykinin) is a product of the kinin system that causes vascular
permeability, smooth muscle contraction, and pain. Option C (Prostaglandin E) is a
lipid mediator involved in inflammation but does not cause endothelial retraction.
Option D (Chemokines) function primarily to induce leukocyte chemotaxis, not
endothelial retraction. PAF is a potent phospholipid mediator released from mast
cells, basophils, and other cells that contributes to the vascular changes in
inflammation.
Question 2: Which hormone suppresses T-cell activity and reduces the
inflammatory response?
A. ACTH
B. Growth hormone
C. Cortisol
D. Prolactin
Correct Answer: C. Cortisol
, Rationale: Cortisol acts to suppress the activity of T cells, which leads to a
decrease in innate immunity and the proinflammatory response. Cortisol also
stimulates the activity of Th2 cells, which increases antibody-mediated immunity.
This immunosuppressive effect is why corticosteroids are used to treat
inflammatory and autoimmune conditions. Option A (ACTH) stimulates cortisol
release but does not directly suppress T cells. Option B (Growth hormone)
generally enhances immune function. Option D (Prolactin) can have
immunostimulatory effects. Cortisol is a glucocorticoid hormone produced by the
adrenal cortex that plays a key role in the stress response and immune regulation.
Question 3: Many neonates have a transient depressed inflammatory response
as a result of which condition?
A. Mast cells are lacking.
B. The respiratory system is too immature to deliver oxygen to tissues.
C. Complement and chemotaxis are deficient.
D. The circulatory system is too immature to perfuse tissues adequately.
Correct Answer: C. Complement and chemotaxis are deficient.
Rationale: Neonates commonly have transiently depressed inflammatory and
immune function partly due to deficiencies in components of the alternative
complement pathway. For example, neutrophils and peripheral blood monocytes
may not be capable of efficient chemotaxis. Option A is incorrect; mast cells are
not lacking in neonates. Option B is incorrect; the respiratory system should be
adequate to oxygenate tissues and would not directly contribute to decreased
immunity. Option D is incorrect; the circulatory system should adequately perfuse
the neonate. The transient depression of the inflammatory response in neonates
contributes to their increased susceptibility to infections, particularly from
encapsulated bacteria.
Question 4: Which cell has a role in developing cell-mediated immunity?
A. Th2
B. CD4
C. Th1
D. CD8
Questions and Correct Answers plus Rationale | New
Update 2026-2027 | SNHU
Question 1: Which chemical mediator derived from mast cells retracts
endothelial cells to increase vascular permeability and to cause leukocyte
adhesion to endothelial cells?
A. Bradykinin
B. Platelet-activating factor
C. Prostaglandin E
D. Chemokines
Correct Answer: B. Platelet-activating factor
Rationale: The biologic activity of platelet-activating factor (PAF) is virtually
identical to that of leukotrienes. PAF causes endothelial cell retraction to increase
vascular permeability, leukocyte adhesion to endothelium, and platelet activation.
Option A (Bradykinin) is a product of the kinin system that causes vascular
permeability, smooth muscle contraction, and pain. Option C (Prostaglandin E) is a
lipid mediator involved in inflammation but does not cause endothelial retraction.
Option D (Chemokines) function primarily to induce leukocyte chemotaxis, not
endothelial retraction. PAF is a potent phospholipid mediator released from mast
cells, basophils, and other cells that contributes to the vascular changes in
inflammation.
Question 2: Which hormone suppresses T-cell activity and reduces the
inflammatory response?
A. ACTH
B. Growth hormone
C. Cortisol
D. Prolactin
Correct Answer: C. Cortisol
, Rationale: Cortisol acts to suppress the activity of T cells, which leads to a
decrease in innate immunity and the proinflammatory response. Cortisol also
stimulates the activity of Th2 cells, which increases antibody-mediated immunity.
This immunosuppressive effect is why corticosteroids are used to treat
inflammatory and autoimmune conditions. Option A (ACTH) stimulates cortisol
release but does not directly suppress T cells. Option B (Growth hormone)
generally enhances immune function. Option D (Prolactin) can have
immunostimulatory effects. Cortisol is a glucocorticoid hormone produced by the
adrenal cortex that plays a key role in the stress response and immune regulation.
Question 3: Many neonates have a transient depressed inflammatory response
as a result of which condition?
A. Mast cells are lacking.
B. The respiratory system is too immature to deliver oxygen to tissues.
C. Complement and chemotaxis are deficient.
D. The circulatory system is too immature to perfuse tissues adequately.
Correct Answer: C. Complement and chemotaxis are deficient.
Rationale: Neonates commonly have transiently depressed inflammatory and
immune function partly due to deficiencies in components of the alternative
complement pathway. For example, neutrophils and peripheral blood monocytes
may not be capable of efficient chemotaxis. Option A is incorrect; mast cells are
not lacking in neonates. Option B is incorrect; the respiratory system should be
adequate to oxygenate tissues and would not directly contribute to decreased
immunity. Option D is incorrect; the circulatory system should adequately perfuse
the neonate. The transient depression of the inflammatory response in neonates
contributes to their increased susceptibility to infections, particularly from
encapsulated bacteria.
Question 4: Which cell has a role in developing cell-mediated immunity?
A. Th2
B. CD4
C. Th1
D. CD8
