WGU PATHOPHYSIOLOGY D236 | ACTUAL EXAM QUESTIONS WITH
ACCURATE SOLUTIONS(RATIONALES) 2025/26.
Question 1
What is the fundamental process by which oxygen moves from the alveoli into the bloodstream?
A) Osmosis
B) Active Transport
C) Filtration
D) Diffusion
E) Phagocytosis
Correct Answer: D) Diffusion
Rationale: Diffusion is the passive movement of molecules from an area of higher
concentration to an area of lower concentration. In the lungs, the concentration of oxygen
is high in the alveoli and low in the deoxygenated blood of the pulmonary capillaries. This
concentration gradient drives oxygen to diffuse across the alveolar-capillary membrane
into the blood.
Question 2
A client with lactose intolerance consumes a large amount of milk and subsequently develops
diarrhea. This type of diarrhea, caused by a non-absorbable substance drawing water into the
intestine, is known as:
A) Secretory diarrhea
B) Motility diarrhea
C) Inflammatory diarrhea
D) Osmotic diarrhea
E) Exudative diarrhea
Correct Answer: D) Osmotic diarrhea
Rationale: Osmotic diarrhea occurs when a non-absorbable substance in the intestine, such
as lactose in a lactose-intolerant individual, exerts an osmotic pull, drawing excess water
into the intestinal lumen. This increases the volume and fluidity of the stool, resulting in
diarrhea.
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Question 3
A 72-year-old client presents to the emergency department with acute dyspnea, bilateral pitting
edema, and crackles in the lungs. The provider suspects an exacerbation of heart failure. The
nurse anticipates an order for which specific laboratory test to help confirm this diagnosis?
A) Serum troponin
B) Complete blood count (CBC)
C) Serum B-type Natriuretic Peptide (BNP)
D) Serum creatinine
E) D-dimer
Correct Answer: C) Serum B-type Natriuretic Peptide (BNP)
Rationale: BNP is a hormone released by the heart's ventricles in response to stretching
caused by increased fluid and pressure, which is characteristic of heart failure. An elevated
BNP level is a highly sensitive and specific marker used to diagnose and determine the
severity of heart failure. The higher the BNP, the more severe the heart failure.
Question 4
A nurse is assessing a client with a large accumulation of fluid in the pleural space. The nurse
notes dyspnea, diminished breath sounds on the affected side, and dullness to percussion. This
condition is known as:
A) Pneumothorax
B) Atelectasis
C) Pulmonary Embolism
D) Pneumonia
E) Pleural Effusion
Correct Answer: E) Pleural Effusion
Rationale: A pleural effusion is the buildup of excess fluid between the layers of the pleura
outside the lungs. This fluid compresses the lung tissue, leading to dyspnea (shortness of
breath), diminished or absent breath sounds, and a dull sound on percussion over the area
of the fluid.
Question 5
A client's arterial blood gas (ABG) results are: pH 7.29, PaCO2 55 mmHg, and HCO3 25
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mEq/L. The nurse correctly interprets these values as which acid-base imbalance?
A) Metabolic Acidosis
B) Respiratory Alkalosis
C) Metabolic Alkalosis
D) Respiratory Acidosis
E) Normal ABG
Correct Answer: D) Respiratory Acidosis
Rationale: The pH of 7.29 is acidotic (normal: 7.35-7.45). The PaCO2 of 55 mmHg is high
(normal: 35-45), indicating retention of carbon dioxide, which is the cause of the acidosis.
The HCO3 (bicarbonate) is within the normal range (22-26), indicating that the kidneys
have not yet compensated. This pattern is characteristic of uncompensated respiratory
acidosis, often caused by conditions that impair ventilation like COPD or severe
pneumonia.
Question 6
A client has developed metabolic acidosis. How will the respiratory system attempt to
compensate for this imbalance?
A) By decreasing the rate and depth of breathing to retain CO2.
B) By increasing the rate and depth of breathing to blow off CO2.
C) The respiratory system does not compensate for metabolic imbalances.
D) By causing bronchoconstriction to trap air.
E) By increasing the production of bicarbonate.
Correct Answer: B) By increasing the rate and depth of breathing to blow off CO2.
Rationale: In metabolic acidosis, there is an excess of acid in the body. The lungs
compensate by trying to reduce the amount of acid. They do this by increasing the rate and
depth of ventilation (hyperventilation, sometimes called Kussmaul's respirations). This
process expels more carbon dioxide (an acid), which helps to raise the blood pH back
toward a normal level.
Question 7
If an individual inherits the same allele for a particular trait from both their mother and father
(e.g., both alleles for blue eyes), their genotype for that trait is described as:
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A) Heterozygous
B) Hemizygous
C) Dominant
D) Recessive
E) Homozygous
Correct Answer: E) Homozygous
Rationale: Homozygous refers to a genetic condition where an individual has inherited the
same alleles of a particular gene from both parents. This can be homozygous dominant
(e.g., HH) or homozygous recessive (e.g., hh). Heterozygous means inheriting different
alleles (e.g., Hh).
Question 8
Which of the following statements accurately describes the intracellular fluid (ICF)
compartment?
A) It is the fluid found in the space between cells.
B) It consists of the fluid contained within the blood vessels.
C) It is the fluid contained within all the body's cells.
D) It makes up about one-third of the body's total water.
E) It is the fluid found in the cerebrospinal space and joints.
Correct Answer: C) It is the fluid contained within all the body's cells.
Rationale: The ICF compartment comprises all the fluid inside the cells of the body. It is
the largest fluid compartment, making up approximately two-thirds of the body's total
water content. The fluid outside the cells is the extracellular fluid (ECF).
Question 9
A deficit of intracellular fluid, which causes body cells to shrink and can lead to symptoms like
confusion and thirst, is known as:
A) Edema
B) Dehydration
C) Overhydration
D) Isotonic fluid loss
E) Hypervolemia
ACCURATE SOLUTIONS(RATIONALES) 2025/26.
Question 1
What is the fundamental process by which oxygen moves from the alveoli into the bloodstream?
A) Osmosis
B) Active Transport
C) Filtration
D) Diffusion
E) Phagocytosis
Correct Answer: D) Diffusion
Rationale: Diffusion is the passive movement of molecules from an area of higher
concentration to an area of lower concentration. In the lungs, the concentration of oxygen
is high in the alveoli and low in the deoxygenated blood of the pulmonary capillaries. This
concentration gradient drives oxygen to diffuse across the alveolar-capillary membrane
into the blood.
Question 2
A client with lactose intolerance consumes a large amount of milk and subsequently develops
diarrhea. This type of diarrhea, caused by a non-absorbable substance drawing water into the
intestine, is known as:
A) Secretory diarrhea
B) Motility diarrhea
C) Inflammatory diarrhea
D) Osmotic diarrhea
E) Exudative diarrhea
Correct Answer: D) Osmotic diarrhea
Rationale: Osmotic diarrhea occurs when a non-absorbable substance in the intestine, such
as lactose in a lactose-intolerant individual, exerts an osmotic pull, drawing excess water
into the intestinal lumen. This increases the volume and fluidity of the stool, resulting in
diarrhea.
,[Type here]
Question 3
A 72-year-old client presents to the emergency department with acute dyspnea, bilateral pitting
edema, and crackles in the lungs. The provider suspects an exacerbation of heart failure. The
nurse anticipates an order for which specific laboratory test to help confirm this diagnosis?
A) Serum troponin
B) Complete blood count (CBC)
C) Serum B-type Natriuretic Peptide (BNP)
D) Serum creatinine
E) D-dimer
Correct Answer: C) Serum B-type Natriuretic Peptide (BNP)
Rationale: BNP is a hormone released by the heart's ventricles in response to stretching
caused by increased fluid and pressure, which is characteristic of heart failure. An elevated
BNP level is a highly sensitive and specific marker used to diagnose and determine the
severity of heart failure. The higher the BNP, the more severe the heart failure.
Question 4
A nurse is assessing a client with a large accumulation of fluid in the pleural space. The nurse
notes dyspnea, diminished breath sounds on the affected side, and dullness to percussion. This
condition is known as:
A) Pneumothorax
B) Atelectasis
C) Pulmonary Embolism
D) Pneumonia
E) Pleural Effusion
Correct Answer: E) Pleural Effusion
Rationale: A pleural effusion is the buildup of excess fluid between the layers of the pleura
outside the lungs. This fluid compresses the lung tissue, leading to dyspnea (shortness of
breath), diminished or absent breath sounds, and a dull sound on percussion over the area
of the fluid.
Question 5
A client's arterial blood gas (ABG) results are: pH 7.29, PaCO2 55 mmHg, and HCO3 25
,[Type here]
mEq/L. The nurse correctly interprets these values as which acid-base imbalance?
A) Metabolic Acidosis
B) Respiratory Alkalosis
C) Metabolic Alkalosis
D) Respiratory Acidosis
E) Normal ABG
Correct Answer: D) Respiratory Acidosis
Rationale: The pH of 7.29 is acidotic (normal: 7.35-7.45). The PaCO2 of 55 mmHg is high
(normal: 35-45), indicating retention of carbon dioxide, which is the cause of the acidosis.
The HCO3 (bicarbonate) is within the normal range (22-26), indicating that the kidneys
have not yet compensated. This pattern is characteristic of uncompensated respiratory
acidosis, often caused by conditions that impair ventilation like COPD or severe
pneumonia.
Question 6
A client has developed metabolic acidosis. How will the respiratory system attempt to
compensate for this imbalance?
A) By decreasing the rate and depth of breathing to retain CO2.
B) By increasing the rate and depth of breathing to blow off CO2.
C) The respiratory system does not compensate for metabolic imbalances.
D) By causing bronchoconstriction to trap air.
E) By increasing the production of bicarbonate.
Correct Answer: B) By increasing the rate and depth of breathing to blow off CO2.
Rationale: In metabolic acidosis, there is an excess of acid in the body. The lungs
compensate by trying to reduce the amount of acid. They do this by increasing the rate and
depth of ventilation (hyperventilation, sometimes called Kussmaul's respirations). This
process expels more carbon dioxide (an acid), which helps to raise the blood pH back
toward a normal level.
Question 7
If an individual inherits the same allele for a particular trait from both their mother and father
(e.g., both alleles for blue eyes), their genotype for that trait is described as:
, [Type here]
A) Heterozygous
B) Hemizygous
C) Dominant
D) Recessive
E) Homozygous
Correct Answer: E) Homozygous
Rationale: Homozygous refers to a genetic condition where an individual has inherited the
same alleles of a particular gene from both parents. This can be homozygous dominant
(e.g., HH) or homozygous recessive (e.g., hh). Heterozygous means inheriting different
alleles (e.g., Hh).
Question 8
Which of the following statements accurately describes the intracellular fluid (ICF)
compartment?
A) It is the fluid found in the space between cells.
B) It consists of the fluid contained within the blood vessels.
C) It is the fluid contained within all the body's cells.
D) It makes up about one-third of the body's total water.
E) It is the fluid found in the cerebrospinal space and joints.
Correct Answer: C) It is the fluid contained within all the body's cells.
Rationale: The ICF compartment comprises all the fluid inside the cells of the body. It is
the largest fluid compartment, making up approximately two-thirds of the body's total
water content. The fluid outside the cells is the extracellular fluid (ECF).
Question 9
A deficit of intracellular fluid, which causes body cells to shrink and can lead to symptoms like
confusion and thirst, is known as:
A) Edema
B) Dehydration
C) Overhydration
D) Isotonic fluid loss
E) Hypervolemia
