NURS 5315 ADVANCED
PATHOPHYSIOLOGY UTA REVIEW SHEET
2026 PRACTICE SOLUTIONS GRADED A+
⩥ Depolarization. Answer: movement of the intracellular charge towards
zero (more positive charge)
Voltage gated Na channels open and allow Na to enter the cell -> voltage
inside the cell moves towards zero
⩥ Repolarization. Answer: Once the intracellular charge reaches zero,
the negative polarity of the inside of the cell is restored back to its
baseline of -70 to -85 mV
-Na channels close, K channels open
⩥ Hyperpolarization. Answer: when the cell's resting membrane
potential is greater than -85mV. Is less excitable, because there is a
greater distance between the resting membrane potential and the
threshold potential.
⩥ In order for the action potential to be sucessful. Answer: t has to
depolarize by 15-20 mV (threshold potential) to reach -55 to -65 mV.
,⩥ An alteration in action potential may result from. Answer: neurologic
diseases, muscle disease or electrolyte imbalances.
⩥ What is the main protein responsible for maintaining the correct
balance of extracellular Na and intracellular K, which is needed for
cellular excitation and membrane conductivity.. Answer: Na+-K+
ATPase
⩥ Resting membrane potential. Answer: when the cell is in a nonexcited
state and is at -70 to -85 mV.
⩥ Refractory Period. Answer: is a period of time during most of the
action potential which the cell membrane resists stimulation and it
cannot depolarize
⩥ Absolute refractory period. Answer: occurs when the membrane will
not respond to ANY stimulus no matter how strong.
⩥ Relative Refractory Period. Answer: occurs when the membrane is
repolarizing and will only respond to a very strong stimulus.
⩥ Hyperpolarized. Answer: when the cell's resting membrane potential
is greater than -85mV.
Is less excitable, because there is a greater distance between the resting
membrane potential and the threshold potential.
,⩥ Hypopolarized. Answer: when the cell's resting membrane potential is
closer to zero, for instance it is -65mV.
Is more excitable because the resting membrane potential is closer to the
threshold potential, there is less distance between them.
⩥ Action potential altered by hypokalemia. Answer: (serum outside of
cell is low)
-Hyperpolarized (cell becomes more negative, ex: -100)
-Affects the resting membrane potential of cells
-The cell is less likely to depolarize and transmit impulses
Can cause a decrease in neuromuscular excitability and leads to
weakness, smooth muscle atony, paresthesias, and cardiac dysrhythmias
⩥ Action potential altered by hyperkalemia. Answer: Hypopolarized
-Also has an effect on the resting membrane potential
-If the ECF potassium increases without any change in the ICF
potassium levels, the resting membrane potential of the cell becomes
more positive.
-The cells are more excitable and conduct impulses more easily and
more quickly because the resting membrane potential is closer to the
threshold potential. Therefore, the person will have peak T waves on
EKG.
-As potassium rises, the resting membrane potential will continue to
become more positive and it will eventually become equal to the
, threshold potential. As this happens the EKG will show a widening QRS
complex. If the resting membrane potential equals the threshold
potential, an action potential will not be generated and cardiac standstill
will occur. Paralysis and paresthesias may also occur.
⩥ Action potential altered by hypocalcemia. Answer: -Causes an
increase in the cell permeability to Na causing a progressive
depolarization
-Causes the RMP and the TP to be closer to one another & making it
easier to initiate an action potential - the cells are more excitable.
-Results in tetany, hyperreflexia, circumoral paresthesias, seizures,
dysrhythmias
⩥ Action potential altered by hypercalcemia. Answer: -Causes a
decrease in cell permeability to Na
-Causes the RMP and the TP to increase in distance - the cells are less
excitable and requires more of a stimulus to initiate an action potential.
-Leads to weakness, hyporeflexia, fatigue, lethargy, confusion,
encephalopathy, a shortened QT segment and depressed widened T
waves on EKG.
⩥ Atrophy. Answer: decrease or shrinkage in the size of the cell
-Imbalance between protein synthesis and degradation, , reduction of the
intracellular contents, also includes a self-eating process called
autophagy.
PATHOPHYSIOLOGY UTA REVIEW SHEET
2026 PRACTICE SOLUTIONS GRADED A+
⩥ Depolarization. Answer: movement of the intracellular charge towards
zero (more positive charge)
Voltage gated Na channels open and allow Na to enter the cell -> voltage
inside the cell moves towards zero
⩥ Repolarization. Answer: Once the intracellular charge reaches zero,
the negative polarity of the inside of the cell is restored back to its
baseline of -70 to -85 mV
-Na channels close, K channels open
⩥ Hyperpolarization. Answer: when the cell's resting membrane
potential is greater than -85mV. Is less excitable, because there is a
greater distance between the resting membrane potential and the
threshold potential.
⩥ In order for the action potential to be sucessful. Answer: t has to
depolarize by 15-20 mV (threshold potential) to reach -55 to -65 mV.
,⩥ An alteration in action potential may result from. Answer: neurologic
diseases, muscle disease or electrolyte imbalances.
⩥ What is the main protein responsible for maintaining the correct
balance of extracellular Na and intracellular K, which is needed for
cellular excitation and membrane conductivity.. Answer: Na+-K+
ATPase
⩥ Resting membrane potential. Answer: when the cell is in a nonexcited
state and is at -70 to -85 mV.
⩥ Refractory Period. Answer: is a period of time during most of the
action potential which the cell membrane resists stimulation and it
cannot depolarize
⩥ Absolute refractory period. Answer: occurs when the membrane will
not respond to ANY stimulus no matter how strong.
⩥ Relative Refractory Period. Answer: occurs when the membrane is
repolarizing and will only respond to a very strong stimulus.
⩥ Hyperpolarized. Answer: when the cell's resting membrane potential
is greater than -85mV.
Is less excitable, because there is a greater distance between the resting
membrane potential and the threshold potential.
,⩥ Hypopolarized. Answer: when the cell's resting membrane potential is
closer to zero, for instance it is -65mV.
Is more excitable because the resting membrane potential is closer to the
threshold potential, there is less distance between them.
⩥ Action potential altered by hypokalemia. Answer: (serum outside of
cell is low)
-Hyperpolarized (cell becomes more negative, ex: -100)
-Affects the resting membrane potential of cells
-The cell is less likely to depolarize and transmit impulses
Can cause a decrease in neuromuscular excitability and leads to
weakness, smooth muscle atony, paresthesias, and cardiac dysrhythmias
⩥ Action potential altered by hyperkalemia. Answer: Hypopolarized
-Also has an effect on the resting membrane potential
-If the ECF potassium increases without any change in the ICF
potassium levels, the resting membrane potential of the cell becomes
more positive.
-The cells are more excitable and conduct impulses more easily and
more quickly because the resting membrane potential is closer to the
threshold potential. Therefore, the person will have peak T waves on
EKG.
-As potassium rises, the resting membrane potential will continue to
become more positive and it will eventually become equal to the
, threshold potential. As this happens the EKG will show a widening QRS
complex. If the resting membrane potential equals the threshold
potential, an action potential will not be generated and cardiac standstill
will occur. Paralysis and paresthesias may also occur.
⩥ Action potential altered by hypocalcemia. Answer: -Causes an
increase in the cell permeability to Na causing a progressive
depolarization
-Causes the RMP and the TP to be closer to one another & making it
easier to initiate an action potential - the cells are more excitable.
-Results in tetany, hyperreflexia, circumoral paresthesias, seizures,
dysrhythmias
⩥ Action potential altered by hypercalcemia. Answer: -Causes a
decrease in cell permeability to Na
-Causes the RMP and the TP to increase in distance - the cells are less
excitable and requires more of a stimulus to initiate an action potential.
-Leads to weakness, hyporeflexia, fatigue, lethargy, confusion,
encephalopathy, a shortened QT segment and depressed widened T
waves on EKG.
⩥ Atrophy. Answer: decrease or shrinkage in the size of the cell
-Imbalance between protein synthesis and degradation, , reduction of the
intracellular contents, also includes a self-eating process called
autophagy.
