NR 507 Week 8 Final Exam – 200 Practice Questions with
Correct Answers & Explanations
1. What is the primary mechanism of tissue injury in Type I hypersensitivity reactions?
- A) Antibody-dependent cell-mediated cytotoxicity
- B) Immune complex deposition in blood vessels
- C) IgE-mediated mast cell degranulation
- D) T lymphocyte-mediated direct cytotoxicity
Answer: C) IgE-mediated mast cell degranulation
Explanation: Type I (immediate) hypersensitivity is mediated by IgE antibodies binding to mast cells and
basophils, causing degranulation and release of histamine, leukotrienes, and other inflammatory
mediators. This underlies allergic reactions such as anaphylaxis, asthma, and hay fever.
2. A 65-year-old man is admitted to the intensive care unit after a triple coronary artery bypass graft.
Postoperative lactic acid levels were normal but are now rising. The increased level could be an
indication of:
- A) Excessive sedation
- B) Bowel ischemia
- C) Excessive volume infusion
- D) Mild hypothermia
Answer: B) Bowel ischemia
Explanation: Rising lactic acid levels in a postoperative patient should raise suspicion for mesenteric or
bowel ischemia. Lactic acidosis results from anaerobic metabolism due to inadequate tissue perfusion.
Bowel ischemia can occur as a complication of cardiac surgery due to hypoperfusion or emboli.
,3. Which of the following describes how the body compensates for anemia?
- A) Increasing rate and depth of breathing
- B) Decreasing capillary vasoconstriction
- C) Hemoglobin holding more firmly onto oxygen
- D) Kidneys releasing more erythropoietin
Answer: D) Kidneys releasing more erythropoietin
Explanation: In anemia, decreased oxygen delivery to the kidneys stimulates the release of
erythropoietin (EPO), which increases red blood cell production. Other compensatory mechanisms
include increased cardiac output and decreased blood viscosity.
4. The ability of a pathogen to invade and multiply in the host is referred to as:
- A) Infectivity
- B) Toxigenicity
- C) Pathogenicity
- D) Virulence
Answer: A) Infectivity
Explanation: Infectivity is the ability of a pathogen to establish infection by invading and multiplying in
the host. Pathogenicity is the ability to cause disease, while virulence refers to the degree of
pathogenicity. Toxigenicity is the ability to produce toxins.
5. What is the major virus involved in the development of cervical cancer?
- A) Herpes simplex virus type 6
- B) Herpes simplex virus type 2
,- C) Human papillomavirus
- D) Human immunodeficiency virus
Answer: C) Human papillomavirus
Explanation: Persistent infection with high-risk human papillomavirus (HPV) types, particularly HPV-16
and HPV-18, is the primary cause of cervical cancer. HPV oncoproteins E6 and E7 inactivate tumor
suppressor proteins p53 and Rb, leading to cellular transformation.
6. Which statement accurately describes childhood asthma?
- A) Obstructive airway disease with reversible airflow obstruction, bronchial hyperreactivity, and
inflammation
- B) Pulmonary disease characterized by severe hypoxemia and decreased compliance
- C) Disorder with abnormal protein expression producing viscous mucus
- D) Disease characterized by atelectasis and surfactant deficiency
Answer: A) Obstructive airway disease with reversible airflow obstruction, bronchial hyperreactivity, and
inflammation
Explanation: Childhood asthma is a chronic inflammatory disorder of the airways characterized by
reversible airflow obstruction, airway hyperresponsiveness, and inflammation. Triggers cause
bronchoconstriction, mucosal edema, and increased mucus production.
7. The tonic neck reflex observed in a newborn should no longer be obtainable by what age?
- A) 2 years
- B) 1 year
- C) 10 months
- D) 5 months
, Answer: D) 5 months
Explanation: The tonic neck reflex (also called the fencing reflex) typically appears at birth and should
disappear by 4-6 months of age. Persistence beyond this period may indicate neurological impairment.
8. Cystic fibrosis is caused by a mutation in which gene?
- A) CFTR gene on chromosome 7
- B) BRCA1 gene on chromosome 17
- C) HBB gene on chromosome 11
- D) FMR1 gene on chromosome X
Answer: A) CFTR gene on chromosome 7
Explanation: Cystic fibrosis is an autosomal recessive disorder caused by mutations in the CFTR (cystic
fibrosis transmembrane conductance regulator) gene on chromosome 7. This leads to defective chloride
channel function, resulting in thick, viscous secretions in the lungs, pancreas, and other organs.
9. Obesity creates a greater risk for dehydration because:
- A) Adipose cells contain little water as fat is water repelling
- B) Metabolic rate of obese adults is slower
- C) Urine output of obese adults is higher
- D) Thirst receptors do not function effectively
Answer: A) Adipose cells contain little water as fat is water repelling
Explanation: Adipose tissue has lower water content compared to lean tissue. Obese individuals have
proportionally more fat mass and less total body water as a percentage of body weight, increasing their
risk of dehydration.
Correct Answers & Explanations
1. What is the primary mechanism of tissue injury in Type I hypersensitivity reactions?
- A) Antibody-dependent cell-mediated cytotoxicity
- B) Immune complex deposition in blood vessels
- C) IgE-mediated mast cell degranulation
- D) T lymphocyte-mediated direct cytotoxicity
Answer: C) IgE-mediated mast cell degranulation
Explanation: Type I (immediate) hypersensitivity is mediated by IgE antibodies binding to mast cells and
basophils, causing degranulation and release of histamine, leukotrienes, and other inflammatory
mediators. This underlies allergic reactions such as anaphylaxis, asthma, and hay fever.
2. A 65-year-old man is admitted to the intensive care unit after a triple coronary artery bypass graft.
Postoperative lactic acid levels were normal but are now rising. The increased level could be an
indication of:
- A) Excessive sedation
- B) Bowel ischemia
- C) Excessive volume infusion
- D) Mild hypothermia
Answer: B) Bowel ischemia
Explanation: Rising lactic acid levels in a postoperative patient should raise suspicion for mesenteric or
bowel ischemia. Lactic acidosis results from anaerobic metabolism due to inadequate tissue perfusion.
Bowel ischemia can occur as a complication of cardiac surgery due to hypoperfusion or emboli.
,3. Which of the following describes how the body compensates for anemia?
- A) Increasing rate and depth of breathing
- B) Decreasing capillary vasoconstriction
- C) Hemoglobin holding more firmly onto oxygen
- D) Kidneys releasing more erythropoietin
Answer: D) Kidneys releasing more erythropoietin
Explanation: In anemia, decreased oxygen delivery to the kidneys stimulates the release of
erythropoietin (EPO), which increases red blood cell production. Other compensatory mechanisms
include increased cardiac output and decreased blood viscosity.
4. The ability of a pathogen to invade and multiply in the host is referred to as:
- A) Infectivity
- B) Toxigenicity
- C) Pathogenicity
- D) Virulence
Answer: A) Infectivity
Explanation: Infectivity is the ability of a pathogen to establish infection by invading and multiplying in
the host. Pathogenicity is the ability to cause disease, while virulence refers to the degree of
pathogenicity. Toxigenicity is the ability to produce toxins.
5. What is the major virus involved in the development of cervical cancer?
- A) Herpes simplex virus type 6
- B) Herpes simplex virus type 2
,- C) Human papillomavirus
- D) Human immunodeficiency virus
Answer: C) Human papillomavirus
Explanation: Persistent infection with high-risk human papillomavirus (HPV) types, particularly HPV-16
and HPV-18, is the primary cause of cervical cancer. HPV oncoproteins E6 and E7 inactivate tumor
suppressor proteins p53 and Rb, leading to cellular transformation.
6. Which statement accurately describes childhood asthma?
- A) Obstructive airway disease with reversible airflow obstruction, bronchial hyperreactivity, and
inflammation
- B) Pulmonary disease characterized by severe hypoxemia and decreased compliance
- C) Disorder with abnormal protein expression producing viscous mucus
- D) Disease characterized by atelectasis and surfactant deficiency
Answer: A) Obstructive airway disease with reversible airflow obstruction, bronchial hyperreactivity, and
inflammation
Explanation: Childhood asthma is a chronic inflammatory disorder of the airways characterized by
reversible airflow obstruction, airway hyperresponsiveness, and inflammation. Triggers cause
bronchoconstriction, mucosal edema, and increased mucus production.
7. The tonic neck reflex observed in a newborn should no longer be obtainable by what age?
- A) 2 years
- B) 1 year
- C) 10 months
- D) 5 months
, Answer: D) 5 months
Explanation: The tonic neck reflex (also called the fencing reflex) typically appears at birth and should
disappear by 4-6 months of age. Persistence beyond this period may indicate neurological impairment.
8. Cystic fibrosis is caused by a mutation in which gene?
- A) CFTR gene on chromosome 7
- B) BRCA1 gene on chromosome 17
- C) HBB gene on chromosome 11
- D) FMR1 gene on chromosome X
Answer: A) CFTR gene on chromosome 7
Explanation: Cystic fibrosis is an autosomal recessive disorder caused by mutations in the CFTR (cystic
fibrosis transmembrane conductance regulator) gene on chromosome 7. This leads to defective chloride
channel function, resulting in thick, viscous secretions in the lungs, pancreas, and other organs.
9. Obesity creates a greater risk for dehydration because:
- A) Adipose cells contain little water as fat is water repelling
- B) Metabolic rate of obese adults is slower
- C) Urine output of obese adults is higher
- D) Thirst receptors do not function effectively
Answer: A) Adipose cells contain little water as fat is water repelling
Explanation: Adipose tissue has lower water content compared to lean tissue. Obese individuals have
proportionally more fat mass and less total body water as a percentage of body weight, increasing their
risk of dehydration.
