Comprehensive NSG 5003 Pathophysiology, Cellular Injury,
Electrolyte Imbalances, Acid–Base Balance, and Immune Responses
Exam Questions and Correct Answers
1. Understanding the various steps of proteolytic cascades, such as caspase-mediated
apoptosis and complement cascades, may be useful in designing drug therapy for which
human diseases?
a) Infectious diseases only
b) Autoimmune and malignant disorders
c) Metabolic disorders
d) Genetic disorders
ANS: b)
Proteolytic cascades regulate inflammation, immune responses, and programmed cell
death. Dysregulation of these cascades contributes to autoimmune diseases and cancer
progression. Targeting specific steps allows for selective suppression or activation of
immune and apoptotic pathways. This knowledge is critical for immunotherapy and
anticancer drug development.
2. Why is it possible for potassium to diffuse easily into and out of cells?
a) Potassium uses active transport exclusively
b) The resting plasma membrane is more permeable to potassium
c) Potassium is electrically neutral
d) Potassium concentration is equal inside and outside the cell
ANS: b)
Cell membranes contain numerous potassium leak channels that allow potassium ions to
move freely. This high permeability plays a major role in establishing the resting
membrane potential. Small changes in potassium concentration can significantly alter
cellular excitability. This is especially important in nerve and muscle cells.
3. The loss of adenosine triphosphate (ATP) during ischemia causes cells to:
a) Shrink due to potassium loss
b) Undergo immediate apoptosis
c) Swell because of the influx of sodium chloride
d) Increase protein synthesis
ANS: c)
ATP depletion impairs the sodium-potassium pump, allowing sodium to accumulate
inside the cell. Chloride follows sodium, increasing intracellular osmotic pressure. Water
then enters the cell, causing swelling. This is an early reversible sign of cellular injury.
4. Free radicals play a major role in the initiation and progression of which diseases?
a) Endocrine disorders
b) Gastrointestinal disorders
c) Cardiovascular diseases such as hypertension and ischemic heart disease
d) Autoimmune disorders only
ANS: c)
Free radicals damage lipids, proteins, and DNA through oxidative stress. In
, cardiovascular disease, they contribute to endothelial dysfunction and atherosclerosis.
Oxidative injury worsens ischemia and reperfusion damage. Antioxidants are often
studied for therapeutic benefit.
5. Free radicals cause cell damage by:
a) Binding to receptors
b) Giving up an electron, which causes injury to the chemical bonds of the cell membrane
c) Increasing ATP production
d) Enhancing DNA replication
ANS: b)
Free radicals are unstable molecules that donate electrons, disrupting molecular bonds.
This damages cell membranes, enzymes, and nucleic acids. Lipid peroxidation is a
common result, weakening membrane integrity. Accumulated damage can lead to cell
death.
6. What is a consequence of plasma membrane damage to the mitochondria?
a) Increased ATP synthesis
b) Influx of calcium ions halts ATP production
c) Enhanced oxidative phosphorylation
d) Increased glucose uptake
ANS: b)
Mitochondrial membrane damage allows excessive calcium entry. High calcium levels
inhibit oxidative phosphorylation enzymes. This results in reduced ATP generation and
worsens cellular injury. Mitochondrial failure is a key step toward irreversible damage.
7. What is a consequence of leakage of lysosomal enzymes during chemical injury?
a) Increased protein synthesis
b) Enzymatic digestion of the nucleus and nucleolus occurs, halting DNA synthesis
c) Stabilization of the cell membrane
d) Activation of repair mechanisms
ANS: b)
Lysosomes contain hydrolytic enzymes capable of digesting cellular components. When
released, these enzymes degrade DNA and nuclear structures. This halts replication and
transcription. Extensive damage leads to necrosis.
8. Which statement best describes the characteristics of apoptosis?
a) Inflammatory cell death affecting tissue regions
b) Random destruction of cell membranes
c) Programmed cell death of scattered, single cells
d) Cell swelling and rupture
ANS: c)
Apoptosis is a controlled, energy-dependent process. It eliminates damaged or
unnecessary cells without triggering inflammation. Cells shrink, fragment, and are
phagocytosed. This process is essential for normal development and immune regulation.
9. During cell injury caused by hypoxia, an increase in osmotic pressure occurs within the
cell because:
a) Potassium exits the cell
b) Sodium chloride enters the cell
c) Calcium is actively pumped out
d) Proteins leave the cytoplasm
, ANS: b)
Hypoxia reduces ATP availability, impairing ion pumps. Sodium accumulates
intracellularly, followed by chloride ions. This increases osmotic pressure, drawing water
into the cell. The result is cellular swelling.
10. What physiologic change occurs during heat exhaustion?
a) Hemodilution
b) Metabolic alkalosis
c) Hemoconcentration occurs because of the loss of salt and water
d) Increased plasma volume
ANS: c)
Heat exhaustion results from excessive sweating and fluid loss. Both water and
electrolytes are depleted. This causes reduced plasma volume and increased blood
concentration. If untreated, it may progress to heat stroke.
11. In hypoxic injury, sodium enters the cell and causes swelling because:
a) Chloride channels are overactive
b) ATP is insufficient to maintain the pump that keeps sodium out of the cell
c) Calcium replaces sodium
d) Potassium pumps are overstimulated
ANS: b)
The sodium-potassium ATPase requires ATP to function. Hypoxia reduces ATP
production. Without adequate pump activity, sodium accumulates inside the cell. Water
follows, causing swelling.
12. What is the cause of free calcium in the cytosol that damages cell membranes by
uncontrolled enzyme activation?
a) Increased dietary calcium
b) Depletion of ATP normally pumps calcium from the cell
c) Enhanced mitochondrial uptake
d) Reduced sodium permeability
ANS: b)
ATP-dependent calcium pumps maintain low intracellular calcium levels. When ATP is
depleted, calcium accumulates in the cytosol. Elevated calcium activates destructive
enzymes. This damages membranes and cellular structures.
13. What is the single most common cause of cellular injury?
a) Infection
b) Chemical toxins
c) Hypoxic injury
d) Genetic mutations
ANS: c)
Hypoxia deprives cells of oxygen needed for ATP production. This disrupts energy-
dependent processes. It commonly occurs in ischemia, respiratory failure, and anemia.
Prolonged hypoxia leads to irreversible injury.
14. During cell injury caused by hypoxia, sodium and water move into the cell because:
a) The membrane becomes impermeable
b) Protein synthesis increases
c) The sodium pump cannot function due to decreased ATP
d) Potassium concentration increases
Electrolyte Imbalances, Acid–Base Balance, and Immune Responses
Exam Questions and Correct Answers
1. Understanding the various steps of proteolytic cascades, such as caspase-mediated
apoptosis and complement cascades, may be useful in designing drug therapy for which
human diseases?
a) Infectious diseases only
b) Autoimmune and malignant disorders
c) Metabolic disorders
d) Genetic disorders
ANS: b)
Proteolytic cascades regulate inflammation, immune responses, and programmed cell
death. Dysregulation of these cascades contributes to autoimmune diseases and cancer
progression. Targeting specific steps allows for selective suppression or activation of
immune and apoptotic pathways. This knowledge is critical for immunotherapy and
anticancer drug development.
2. Why is it possible for potassium to diffuse easily into and out of cells?
a) Potassium uses active transport exclusively
b) The resting plasma membrane is more permeable to potassium
c) Potassium is electrically neutral
d) Potassium concentration is equal inside and outside the cell
ANS: b)
Cell membranes contain numerous potassium leak channels that allow potassium ions to
move freely. This high permeability plays a major role in establishing the resting
membrane potential. Small changes in potassium concentration can significantly alter
cellular excitability. This is especially important in nerve and muscle cells.
3. The loss of adenosine triphosphate (ATP) during ischemia causes cells to:
a) Shrink due to potassium loss
b) Undergo immediate apoptosis
c) Swell because of the influx of sodium chloride
d) Increase protein synthesis
ANS: c)
ATP depletion impairs the sodium-potassium pump, allowing sodium to accumulate
inside the cell. Chloride follows sodium, increasing intracellular osmotic pressure. Water
then enters the cell, causing swelling. This is an early reversible sign of cellular injury.
4. Free radicals play a major role in the initiation and progression of which diseases?
a) Endocrine disorders
b) Gastrointestinal disorders
c) Cardiovascular diseases such as hypertension and ischemic heart disease
d) Autoimmune disorders only
ANS: c)
Free radicals damage lipids, proteins, and DNA through oxidative stress. In
, cardiovascular disease, they contribute to endothelial dysfunction and atherosclerosis.
Oxidative injury worsens ischemia and reperfusion damage. Antioxidants are often
studied for therapeutic benefit.
5. Free radicals cause cell damage by:
a) Binding to receptors
b) Giving up an electron, which causes injury to the chemical bonds of the cell membrane
c) Increasing ATP production
d) Enhancing DNA replication
ANS: b)
Free radicals are unstable molecules that donate electrons, disrupting molecular bonds.
This damages cell membranes, enzymes, and nucleic acids. Lipid peroxidation is a
common result, weakening membrane integrity. Accumulated damage can lead to cell
death.
6. What is a consequence of plasma membrane damage to the mitochondria?
a) Increased ATP synthesis
b) Influx of calcium ions halts ATP production
c) Enhanced oxidative phosphorylation
d) Increased glucose uptake
ANS: b)
Mitochondrial membrane damage allows excessive calcium entry. High calcium levels
inhibit oxidative phosphorylation enzymes. This results in reduced ATP generation and
worsens cellular injury. Mitochondrial failure is a key step toward irreversible damage.
7. What is a consequence of leakage of lysosomal enzymes during chemical injury?
a) Increased protein synthesis
b) Enzymatic digestion of the nucleus and nucleolus occurs, halting DNA synthesis
c) Stabilization of the cell membrane
d) Activation of repair mechanisms
ANS: b)
Lysosomes contain hydrolytic enzymes capable of digesting cellular components. When
released, these enzymes degrade DNA and nuclear structures. This halts replication and
transcription. Extensive damage leads to necrosis.
8. Which statement best describes the characteristics of apoptosis?
a) Inflammatory cell death affecting tissue regions
b) Random destruction of cell membranes
c) Programmed cell death of scattered, single cells
d) Cell swelling and rupture
ANS: c)
Apoptosis is a controlled, energy-dependent process. It eliminates damaged or
unnecessary cells without triggering inflammation. Cells shrink, fragment, and are
phagocytosed. This process is essential for normal development and immune regulation.
9. During cell injury caused by hypoxia, an increase in osmotic pressure occurs within the
cell because:
a) Potassium exits the cell
b) Sodium chloride enters the cell
c) Calcium is actively pumped out
d) Proteins leave the cytoplasm
, ANS: b)
Hypoxia reduces ATP availability, impairing ion pumps. Sodium accumulates
intracellularly, followed by chloride ions. This increases osmotic pressure, drawing water
into the cell. The result is cellular swelling.
10. What physiologic change occurs during heat exhaustion?
a) Hemodilution
b) Metabolic alkalosis
c) Hemoconcentration occurs because of the loss of salt and water
d) Increased plasma volume
ANS: c)
Heat exhaustion results from excessive sweating and fluid loss. Both water and
electrolytes are depleted. This causes reduced plasma volume and increased blood
concentration. If untreated, it may progress to heat stroke.
11. In hypoxic injury, sodium enters the cell and causes swelling because:
a) Chloride channels are overactive
b) ATP is insufficient to maintain the pump that keeps sodium out of the cell
c) Calcium replaces sodium
d) Potassium pumps are overstimulated
ANS: b)
The sodium-potassium ATPase requires ATP to function. Hypoxia reduces ATP
production. Without adequate pump activity, sodium accumulates inside the cell. Water
follows, causing swelling.
12. What is the cause of free calcium in the cytosol that damages cell membranes by
uncontrolled enzyme activation?
a) Increased dietary calcium
b) Depletion of ATP normally pumps calcium from the cell
c) Enhanced mitochondrial uptake
d) Reduced sodium permeability
ANS: b)
ATP-dependent calcium pumps maintain low intracellular calcium levels. When ATP is
depleted, calcium accumulates in the cytosol. Elevated calcium activates destructive
enzymes. This damages membranes and cellular structures.
13. What is the single most common cause of cellular injury?
a) Infection
b) Chemical toxins
c) Hypoxic injury
d) Genetic mutations
ANS: c)
Hypoxia deprives cells of oxygen needed for ATP production. This disrupts energy-
dependent processes. It commonly occurs in ischemia, respiratory failure, and anemia.
Prolonged hypoxia leads to irreversible injury.
14. During cell injury caused by hypoxia, sodium and water move into the cell because:
a) The membrane becomes impermeable
b) Protein synthesis increases
c) The sodium pump cannot function due to decreased ATP
d) Potassium concentration increases
