PSL 425 FINAL EXAM 2026/2027 ACTUAL QUESTIONS WITH
VERIFIED ANSWERS ALREADY GRADED A+.
The resting membrane potential is mainly determined by:
a. The sodium gradient
b. The chloride gradient
c. The potassium gradient
d. The calcium gradient - (ANSWER)The potassium gradient
The net outward flow of chloride would best be described as a:
a. Equilibrium Current
b. Inward current
c. Outward current
d. Positive Current - (ANSWER)Inward current
What does the Nernst Equation predict for any concentration gradient of a particular ion across a
membrane?
a. The resting membrane potential
b. The permeability of the ion
c. The equilibrium membrane potential
d. The charge of the ion - (ANSWER)The equilibrium membrane potential
When substance is uncharged, as in the case of glucose, when can equilibrium occur?
a. Only when the concentration is equal on the two sides of the membrane
b. Equilibrium can never occur in this instance
c. Only when the voltage different is zero
,PSL 425 FINAL EXAM 2026/2027 ACTUAL QUESTIONS WITH
VERIFIED ANSWERS ALREADY GRADED A+.
d. Only when the external concentration matches the internal concentration of potassium -
(ANSWER)Only when the concentration is equal on the two sides of the membrane
Which answer correctly orders the Nernst potentials of a cell at 37 C for potassium, sodium, calcium, and
chloride from depolarized to hyperpolarized?
a. Ca2+ > Na+ > Cl- > K+
b. K+ > Na+ > Ca2+ > Cl-
c. Na+ > Ca2+ > Cl- > K+
d. K+ > Ca2+ > Cl- > Na+ - (ANSWER)Ca2+ > Na+ > Cl- > K+
What is the name for the movement of a single ion species through the membrane?
a. Charge
b. Resistance
c. Voltage
d. Current - (ANSWER)Current
What directions are the chemical driving force (CDF) and the electrical driving force (EDF) for a
hypothetical positive ion (X+) given values below:Extracellular concentration [X-] = 15 mMIntracellular
concentration [X-] = 100 mMMembrane Voltage Vm = -60 mV
a. CDF in & EDF out
b. CDF in & EDF in
c. CDF out & EDF in
d. CDF out & EDF out - (ANSWER)CDF out & EDF in
What would happen to the equilibrium potential of potassium if the extracellular potassium
concentration decreased?
, PSL 425 FINAL EXAM 2026/2027 ACTUAL QUESTIONS WITH
VERIFIED ANSWERS ALREADY GRADED A+.
a. Repolarize
b. Depolarize
c. Hyperpolarize
d. Nothing - (ANSWER)Hyperpolarize
If neither the chemical nor the electrical term in the electrochemical potential energy difference
equation are zero, when can equilibrium occur?
a. When the chemical term is positive and the electrical term is negative
b. When the two terms are equal but of opposite sign
c. Equilibrium can never occur
d. When the chemical term is negative and the electrical term is positive - (ANSWER)When the two
terms are equal but of opposite sign
The net inward flow of potassium would best be described as a:
a. Equilibrium current
b. Positive Current
c. Outward current
d. Negative Current - (ANSWER)Negative current
If the membrane is permeable to multiple monovalent ions and only these ions, the total ionic current
would be the _______ of the individual ionic currents
a. Product
b. Sum of the reciprocal
c. Sum
VERIFIED ANSWERS ALREADY GRADED A+.
The resting membrane potential is mainly determined by:
a. The sodium gradient
b. The chloride gradient
c. The potassium gradient
d. The calcium gradient - (ANSWER)The potassium gradient
The net outward flow of chloride would best be described as a:
a. Equilibrium Current
b. Inward current
c. Outward current
d. Positive Current - (ANSWER)Inward current
What does the Nernst Equation predict for any concentration gradient of a particular ion across a
membrane?
a. The resting membrane potential
b. The permeability of the ion
c. The equilibrium membrane potential
d. The charge of the ion - (ANSWER)The equilibrium membrane potential
When substance is uncharged, as in the case of glucose, when can equilibrium occur?
a. Only when the concentration is equal on the two sides of the membrane
b. Equilibrium can never occur in this instance
c. Only when the voltage different is zero
,PSL 425 FINAL EXAM 2026/2027 ACTUAL QUESTIONS WITH
VERIFIED ANSWERS ALREADY GRADED A+.
d. Only when the external concentration matches the internal concentration of potassium -
(ANSWER)Only when the concentration is equal on the two sides of the membrane
Which answer correctly orders the Nernst potentials of a cell at 37 C for potassium, sodium, calcium, and
chloride from depolarized to hyperpolarized?
a. Ca2+ > Na+ > Cl- > K+
b. K+ > Na+ > Ca2+ > Cl-
c. Na+ > Ca2+ > Cl- > K+
d. K+ > Ca2+ > Cl- > Na+ - (ANSWER)Ca2+ > Na+ > Cl- > K+
What is the name for the movement of a single ion species through the membrane?
a. Charge
b. Resistance
c. Voltage
d. Current - (ANSWER)Current
What directions are the chemical driving force (CDF) and the electrical driving force (EDF) for a
hypothetical positive ion (X+) given values below:Extracellular concentration [X-] = 15 mMIntracellular
concentration [X-] = 100 mMMembrane Voltage Vm = -60 mV
a. CDF in & EDF out
b. CDF in & EDF in
c. CDF out & EDF in
d. CDF out & EDF out - (ANSWER)CDF out & EDF in
What would happen to the equilibrium potential of potassium if the extracellular potassium
concentration decreased?
, PSL 425 FINAL EXAM 2026/2027 ACTUAL QUESTIONS WITH
VERIFIED ANSWERS ALREADY GRADED A+.
a. Repolarize
b. Depolarize
c. Hyperpolarize
d. Nothing - (ANSWER)Hyperpolarize
If neither the chemical nor the electrical term in the electrochemical potential energy difference
equation are zero, when can equilibrium occur?
a. When the chemical term is positive and the electrical term is negative
b. When the two terms are equal but of opposite sign
c. Equilibrium can never occur
d. When the chemical term is negative and the electrical term is positive - (ANSWER)When the two
terms are equal but of opposite sign
The net inward flow of potassium would best be described as a:
a. Equilibrium current
b. Positive Current
c. Outward current
d. Negative Current - (ANSWER)Negative current
If the membrane is permeable to multiple monovalent ions and only these ions, the total ionic current
would be the _______ of the individual ionic currents
a. Product
b. Sum of the reciprocal
c. Sum
