SCI 221 Final Exam V2 | SCI 221 Human
Physiology with Intervention Skill-Based
(ISB) Experiential Learning | Q&A with
Rationale (SCI221 Final Exam) |
Nightingale College
1. A patient presents with severe peripheral edema and a history of heart failure. Which
physiological principle explains the accumulation of fluid in the interstitial space due to
increased hydrostatic pressure?
A. Capillary hydrostatic pressure exceeding blood colloidal osmotic pressure
B. Osmotic pressure exceeding oncotic pressure
C. Decreased permeability of the capillary endothelium
D. Increased lymphatic drainage rate
Correct Answer: A
Rationale: In heart failure, the heart’s inability to pump efficiently leads to a backup of
blood, which increases capillary hydrostatic pressure. When this pressure exceeds the
blood colloidal osmotic pressure (oncotic pressure), fluid is forced out of the vessels and
into the interstitial spaces. Nurses must monitor for this imbalance to implement
appropriate diuretic interventions or fluid restrictions.
,2. During the depolarization phase of an action potential in a neuron, which ion movement is
primarily responsible for the rapid change in membrane potential?
A. Potassium ions exiting the cell
B. Sodium ions entering the cell
C. Chloride ions entering the cell
D. Calcium ions exiting the cell
Correct Answer: B
Rationale: Depolarization occurs when voltage-gated sodium channels open, allowing
sodium ions to rush into the cell following their electrochemical gradient. This influx makes
the inside of the cell more positive, moving the membrane potential toward zero and
beyond. Understanding this process is essential for recognizing how neuro-muscular
blockers or local anesthetics might interfere with signal transmission.
3. A student is reviewing the Renin-Angiotensin-Aldosterone System (RAAS). What is the
primary stimulus that triggers the release of Renin from the juxtaglomerular apparatus?
A. High blood pressure in the afferent arteriole
B. Parasympathetic nervous system activation
C. Increased blood volume
D. Decreased sodium chloride delivery to the macula densa
Correct Answer: D
, Rationale: Renin release is triggered by a drop in blood pressure, sympathetic stimulation,
or a decrease in sodium chloride concentration sensed by the macula densa cells. This
hormone initiates a cascade that ultimately results in the production of Angiotensin II, a
potent vasoconstrictor. Clinical interventions for hypertension often target this system
through ACE inhibitors or ARBs.
4. Which component of the electrocardiogram (EKG) represents the time it takes for an
impulse to travel from the SA node through the AV node to the ventricles?
A. The PR interval
B. The T wave
C. The QRS complex
D. The ST segment
Correct Answer: A
Rationale: The PR interval measures the duration from the start of atrial depolarization to
the start of ventricular depolarization. A prolonged PR interval may indicate a first-degree
heart block, suggesting a delay in conduction through the AV node. Accurate interpretation
of EKG segments is a critical ISB skill for identifying cardiac rhythm disturbances.
5. In a patient experiencing metabolic acidosis, how would the respiratory system
compensate to help restore pH balance?
A. Decreasing the rate and depth of respiration
B. Holding more carbon dioxide in the lungs
Physiology with Intervention Skill-Based
(ISB) Experiential Learning | Q&A with
Rationale (SCI221 Final Exam) |
Nightingale College
1. A patient presents with severe peripheral edema and a history of heart failure. Which
physiological principle explains the accumulation of fluid in the interstitial space due to
increased hydrostatic pressure?
A. Capillary hydrostatic pressure exceeding blood colloidal osmotic pressure
B. Osmotic pressure exceeding oncotic pressure
C. Decreased permeability of the capillary endothelium
D. Increased lymphatic drainage rate
Correct Answer: A
Rationale: In heart failure, the heart’s inability to pump efficiently leads to a backup of
blood, which increases capillary hydrostatic pressure. When this pressure exceeds the
blood colloidal osmotic pressure (oncotic pressure), fluid is forced out of the vessels and
into the interstitial spaces. Nurses must monitor for this imbalance to implement
appropriate diuretic interventions or fluid restrictions.
,2. During the depolarization phase of an action potential in a neuron, which ion movement is
primarily responsible for the rapid change in membrane potential?
A. Potassium ions exiting the cell
B. Sodium ions entering the cell
C. Chloride ions entering the cell
D. Calcium ions exiting the cell
Correct Answer: B
Rationale: Depolarization occurs when voltage-gated sodium channels open, allowing
sodium ions to rush into the cell following their electrochemical gradient. This influx makes
the inside of the cell more positive, moving the membrane potential toward zero and
beyond. Understanding this process is essential for recognizing how neuro-muscular
blockers or local anesthetics might interfere with signal transmission.
3. A student is reviewing the Renin-Angiotensin-Aldosterone System (RAAS). What is the
primary stimulus that triggers the release of Renin from the juxtaglomerular apparatus?
A. High blood pressure in the afferent arteriole
B. Parasympathetic nervous system activation
C. Increased blood volume
D. Decreased sodium chloride delivery to the macula densa
Correct Answer: D
, Rationale: Renin release is triggered by a drop in blood pressure, sympathetic stimulation,
or a decrease in sodium chloride concentration sensed by the macula densa cells. This
hormone initiates a cascade that ultimately results in the production of Angiotensin II, a
potent vasoconstrictor. Clinical interventions for hypertension often target this system
through ACE inhibitors or ARBs.
4. Which component of the electrocardiogram (EKG) represents the time it takes for an
impulse to travel from the SA node through the AV node to the ventricles?
A. The PR interval
B. The T wave
C. The QRS complex
D. The ST segment
Correct Answer: A
Rationale: The PR interval measures the duration from the start of atrial depolarization to
the start of ventricular depolarization. A prolonged PR interval may indicate a first-degree
heart block, suggesting a delay in conduction through the AV node. Accurate interpretation
of EKG segments is a critical ISB skill for identifying cardiac rhythm disturbances.
5. In a patient experiencing metabolic acidosis, how would the respiratory system
compensate to help restore pH balance?
A. Decreasing the rate and depth of respiration
B. Holding more carbon dioxide in the lungs
