BSC 2086 | BSC2086 Exam 2: Anatomy and
Physiology II Updated and Latest Questions and
Correct Answers with Rationale - Florida State
University
1. Which of the following cells in the alveoli is responsible for producing surfactant to prevent
lung collapse?
A. Type I Alveolar cells
B. Alveolar macrophages
C. Type II Alveolar cells
D. Goblet cells
Correct Answer: C
Expert Explanation: Type II alveolar cells are cuboidal epithelial cells found in the
alveolar walls. These cells secrete a detergent-like substance known as surfactant.
Surfactant reduces the surface tension of alveolar fluid, preventing the lungs from
collapsing during expiration. Without enough surfactant, the high surface tension would
cause the alveoli to stick together. Therefore, these cells are critical for maintaining lung
compliance and ease of breathing.
2. According to Boyle’s Law, what is the relationship between gas pressure and gas volume in
a closed container?
A. Pressure and volume are directly proportional
B. Pressure and volume are inversely proportional
C. Volume increases as pressure increases
D. There is no relationship between pressure and volume
Correct Answer: B
Expert Explanation: Boyle’s Law states that at a constant temperature, the pressure of a
gas varies inversely with its volume. When the volume of the thoracic cavity increases, the
intrapulmonary pressure decreases below atmospheric pressure. This pressure gradient
allows air to flow into the lungs during inspiration. Conversely, decreasing the volume
increases the pressure and forces air out. This physical principle is the fundamental basis
for pulmonary ventilation in humans.
3. If a patient has a Tidal Volume of 500 mL, an Inspiratory Reserve Volume of 3000 mL, and
an Expiratory Reserve Volume of 1100 mL, what is their Vital Capacity?
A. 3500 mL
,B. 4100 mL
C. 5800 mL
D. 4600 mL
Correct Answer: D
Expert Explanation: Vital Capacity is the total amount of exchangeable air in the lungs. It
is calculated by adding the Tidal Volume, Inspiratory Reserve Volume, and Expiratory
Reserve Volume together. Using the provided numbers, 500 mL + 3000 mL + 1100 mL
equals 4600 mL. This capacity represents the maximum volume of air a person can exhale
after a maximum inhalation. It does not include the Residual Volume, which always
remains in the lungs.
4. Which factor would cause the oxygen-hemoglobin dissociation curve to shift to the right,
facilitating oxygen unloading?
A. Decreased temperature
B. Increased 2,3-BPG levels
C. Decreased PCO2
D. Increased pH (Alkalosis)
Correct Answer: B
Expert Explanation: A rightward shift in the oxygen-hemoglobin dissociation curve
indicates a lower affinity of hemoglobin for oxygen. This shift occurs when there is an
increase in temperature, PCO2, H+ concentration, or 2,3-BPG. 2,3-BPG is produced by red
blood cells during glycolysis and binds to hemoglobin to promote O2 release. This
mechanism ensures that metabolically active tissues receive more oxygen when needed. In
contrast, decreased temperature or increased pH would shift the curve to the left.
5. Most of the carbon dioxide (CO2) in the blood is transported in which form?
A. Dissolved in plasma
B. As carbaminohemoglobin
C. As carbonic acid in the erythrocytes
D. As bicarbonate ions in plasma
Correct Answer: D
Expert Explanation: Carbon dioxide is transported in the blood through three main
mechanisms. Approximately 7 to 10 percent is dissolved directly in the plasma. Another 20
percent binds to hemoglobin to form carbaminohemoglobin. However, the vast majority,
about 70 percent, is converted into bicarbonate ions. This conversion is facilitated by the
enzyme carbonic anhydrase within the red blood cells.
, 6. During the ‘Chloride Shift,’ what happens to balance the electrical charge as bicarbonate
leaves the red blood cell?
A. Chloride ions move out of the erythrocyte
B. Potassium ions move into the erythrocyte
C. Chloride ions move into the erythrocyte
D. Sodium ions move out of the erythrocyte
Correct Answer: C
Expert Explanation: As bicarbonate ions are generated in the red blood cell, they diffuse
out into the plasma. This loss of negative ions creates an electrical imbalance across the cell
membrane. To compensate, chloride ions move from the plasma into the red blood cell.
This exchange process is specifically known as the chloride shift. It ensures that the cell
remains electrically neutral while transporting carbon dioxide products.
7. Where are the central chemoreceptors located, and what is their primary stimulus?
A. Carotid bodies; respond to low O2
B. Aortic bodies; respond to high CO2
C. Medulla oblongata; respond to H+ in CSF
D. Hypothalamus; respond to blood pressure
Correct Answer: C
Expert Explanation: Central chemoreceptors are located throughout the brainstem,
specifically in the medulla oblongata. They monitor the chemical composition of the
cerebrospinal fluid (CSF) rather than the blood directly. Their primary stimulus is the
concentration of hydrogen ions (H+) resulting from CO2 diffusion. As PCO2 rises in the
blood, CO2 crosses the blood-brain barrier and forms carbonic acid. This triggers the
receptors to increase the rate and depth of ventilation.
8. Which condition is characterized by a high arterial PCO2 and a low blood pH?
A. Respiratory alkalosis
B. Metabolic alkalosis
C. Metabolic acidosis
D. Respiratory acidosis
Correct Answer: D
Expert Explanation: Respiratory acidosis occurs when the lungs cannot remove enough
carbon dioxide produced by the body. This leads to an accumulation of CO2, which
increases the partial pressure (PCO2) in the blood. Excess CO2 reacts with water to form
carbonic acid, which lowers the blood pH. Common causes include hypoventilation,
Physiology II Updated and Latest Questions and
Correct Answers with Rationale - Florida State
University
1. Which of the following cells in the alveoli is responsible for producing surfactant to prevent
lung collapse?
A. Type I Alveolar cells
B. Alveolar macrophages
C. Type II Alveolar cells
D. Goblet cells
Correct Answer: C
Expert Explanation: Type II alveolar cells are cuboidal epithelial cells found in the
alveolar walls. These cells secrete a detergent-like substance known as surfactant.
Surfactant reduces the surface tension of alveolar fluid, preventing the lungs from
collapsing during expiration. Without enough surfactant, the high surface tension would
cause the alveoli to stick together. Therefore, these cells are critical for maintaining lung
compliance and ease of breathing.
2. According to Boyle’s Law, what is the relationship between gas pressure and gas volume in
a closed container?
A. Pressure and volume are directly proportional
B. Pressure and volume are inversely proportional
C. Volume increases as pressure increases
D. There is no relationship between pressure and volume
Correct Answer: B
Expert Explanation: Boyle’s Law states that at a constant temperature, the pressure of a
gas varies inversely with its volume. When the volume of the thoracic cavity increases, the
intrapulmonary pressure decreases below atmospheric pressure. This pressure gradient
allows air to flow into the lungs during inspiration. Conversely, decreasing the volume
increases the pressure and forces air out. This physical principle is the fundamental basis
for pulmonary ventilation in humans.
3. If a patient has a Tidal Volume of 500 mL, an Inspiratory Reserve Volume of 3000 mL, and
an Expiratory Reserve Volume of 1100 mL, what is their Vital Capacity?
A. 3500 mL
,B. 4100 mL
C. 5800 mL
D. 4600 mL
Correct Answer: D
Expert Explanation: Vital Capacity is the total amount of exchangeable air in the lungs. It
is calculated by adding the Tidal Volume, Inspiratory Reserve Volume, and Expiratory
Reserve Volume together. Using the provided numbers, 500 mL + 3000 mL + 1100 mL
equals 4600 mL. This capacity represents the maximum volume of air a person can exhale
after a maximum inhalation. It does not include the Residual Volume, which always
remains in the lungs.
4. Which factor would cause the oxygen-hemoglobin dissociation curve to shift to the right,
facilitating oxygen unloading?
A. Decreased temperature
B. Increased 2,3-BPG levels
C. Decreased PCO2
D. Increased pH (Alkalosis)
Correct Answer: B
Expert Explanation: A rightward shift in the oxygen-hemoglobin dissociation curve
indicates a lower affinity of hemoglobin for oxygen. This shift occurs when there is an
increase in temperature, PCO2, H+ concentration, or 2,3-BPG. 2,3-BPG is produced by red
blood cells during glycolysis and binds to hemoglobin to promote O2 release. This
mechanism ensures that metabolically active tissues receive more oxygen when needed. In
contrast, decreased temperature or increased pH would shift the curve to the left.
5. Most of the carbon dioxide (CO2) in the blood is transported in which form?
A. Dissolved in plasma
B. As carbaminohemoglobin
C. As carbonic acid in the erythrocytes
D. As bicarbonate ions in plasma
Correct Answer: D
Expert Explanation: Carbon dioxide is transported in the blood through three main
mechanisms. Approximately 7 to 10 percent is dissolved directly in the plasma. Another 20
percent binds to hemoglobin to form carbaminohemoglobin. However, the vast majority,
about 70 percent, is converted into bicarbonate ions. This conversion is facilitated by the
enzyme carbonic anhydrase within the red blood cells.
, 6. During the ‘Chloride Shift,’ what happens to balance the electrical charge as bicarbonate
leaves the red blood cell?
A. Chloride ions move out of the erythrocyte
B. Potassium ions move into the erythrocyte
C. Chloride ions move into the erythrocyte
D. Sodium ions move out of the erythrocyte
Correct Answer: C
Expert Explanation: As bicarbonate ions are generated in the red blood cell, they diffuse
out into the plasma. This loss of negative ions creates an electrical imbalance across the cell
membrane. To compensate, chloride ions move from the plasma into the red blood cell.
This exchange process is specifically known as the chloride shift. It ensures that the cell
remains electrically neutral while transporting carbon dioxide products.
7. Where are the central chemoreceptors located, and what is their primary stimulus?
A. Carotid bodies; respond to low O2
B. Aortic bodies; respond to high CO2
C. Medulla oblongata; respond to H+ in CSF
D. Hypothalamus; respond to blood pressure
Correct Answer: C
Expert Explanation: Central chemoreceptors are located throughout the brainstem,
specifically in the medulla oblongata. They monitor the chemical composition of the
cerebrospinal fluid (CSF) rather than the blood directly. Their primary stimulus is the
concentration of hydrogen ions (H+) resulting from CO2 diffusion. As PCO2 rises in the
blood, CO2 crosses the blood-brain barrier and forms carbonic acid. This triggers the
receptors to increase the rate and depth of ventilation.
8. Which condition is characterized by a high arterial PCO2 and a low blood pH?
A. Respiratory alkalosis
B. Metabolic alkalosis
C. Metabolic acidosis
D. Respiratory acidosis
Correct Answer: D
Expert Explanation: Respiratory acidosis occurs when the lungs cannot remove enough
carbon dioxide produced by the body. This leads to an accumulation of CO2, which
increases the partial pressure (PCO2) in the blood. Excess CO2 reacts with water to form
carbonic acid, which lowers the blood pH. Common causes include hypoventilation,
