QUESTIONS AND VERIFIED ANSWERS||
GUARANTEED PASS|| ALREADY GRADED A+||
LATEST UPDATE 2025
If the membrane potential is equal to the equilibrium potential for potassium,
then what would be the direction of the electrochemical force acting on
potassium?
a) inward
b) outward
c) neither direction since there is no force
d) varied from cell to cell
e) varies based on the concentrations of potassium in the ICF and ECF -
ANSWER-C. neither direction since there is no force
The equilibrium for a cation is -20 mV. Which of the following statements
about this cation is true when a cell is at resting membrane potential? (-70 mV)?
a) The chemical driving force is directed into the cell and the electrical force is
directed out of the cell
b) Both the chemical and electrical forces are directed out of the cell
c) The chemical force is directed out of the cell and the electrical force is
directed into the cell
d) Both the chemical and electrical forces are directed into the cell
e) There is insufficient information to answer this question - ANSWER-C. The
chemical force is directed out of the cell and the electrical force is directed into
the cell
,Which is a TRUE statement about the resting membrane potential in a typical
neuron?
a) The membrane potential is closer to the sodium equilibrium potential that to
the potassium equilibrium potential
b) the membrane potential is at equilibrium for both sodium and potassium at
the same time
c) There is no ion movement at resting membrane potential
d) The sodium-potassium pump maintains the sodium and potassium
concentration gradients; having these concentration gradients is critical to
maintaining a steady resting membrane potential
e) more than one of the above is correct - ANSWER-D. The sodium-potassium
pump maintains the sodium and potassium concentration gradients; having
these concentration gradients is critical to maintaining a steady resting
membrane potential
During an action potential in a neuron, the repolarization of the membrane is the
result of:
a) sodium moving out of the cell
b) potassium moving into of the cell
c) sodium moving into the cell
d) potassium moving out of the cell
e) both calcium and sodium moving across the cell membrane - ANSWER-B.
potassium moving out of the cell
Which type of cell junction allows direct movement of substances from the
cytoplasm of one cell to the cytoplasm of an adjacent cell?
Select one:
a. gap junctions
b. desmosomes
c. fusion junctions
,d. tight junctions
e. more than one of the above is correct - ANSWER-A. gap junctions
One way that membrane surface area is increased in absorptive cells is through
increasing the ___________ of the membrane facing the lumen.
Select one:
a. thickness
b. number of protein channels
c. folding
d. number of receptors
e. number of protein carriers - ANSWER-C. folding
Which of the following pairs of characteristics is more likely to make a
substance diffuse through the phospholipid bilayer?
Select one:
a. molecule being large and polar
b. molecule being small and nonpolar
c. molecule being large and nonpolar
d. molecule being large and amphipathic
e. molecule being small and polar - ANSWER-B. molecule being small or non-
polar
Clinically, one can monitor homeostasis of various substances such as ions,
blood gases, and organic solutes by taking a blood sample and analyzing its
plasma. Does knowing a patient's plasma concentration of Na+ tell you its
concentration in the ECF and ICF?
Select one:
a. You would know the concentration of Na+ in the ICF but not the ECF.
, b. You would know the concentration of Na+ in the ECF but not the ICF.
c. You would know the concentration of Na+ in both the ECF and ICF.
d. You would not know the concentration of Na+ in either the ECF or ICF. -
ANSWER-B. You would know the concentration of Na+ in the ECF but not the
ICF.
The first step of the Na+/K+ pump's activity involves the binding of:
Select one:
a. 3 Na+ from the inside of the cell
b. 2 K+ from the inside of the cell
c. 3 Na+ from the outside of the cell
d. 2 K+ from the outside of the cell
e. 3 Na+ and 2 K+ at the same time to their respective binding sites -
ANSWER-A. 3 Na+ from the inside of the cell
Where does the conversion of pyruvate to acetyl CoA occur in a cell?
Select one:
a. in the ribosomes
b. in the mitochondrial matrix
c. in the cytoplasm
d. along the mitochondrial cristae
e. in vaults - ANSWER-B. in the mitochondrial matrix
Chemicals released by metabolically active cells in a tissue will cause:
Select one:
a. relaxation of arteriolar smooth muscle to increase blood flow
b. relaxation of capillary smooth muscle to decrease blood flow
c. contraction of arteriolar smooth muscle to increase blood flow