BIO 152 FINAL EXAM REVIEW QUESTIONS
WITH CORRECT ANSWERS 2025-2026
For a neuron with an initial membrane potential at -70 mV, an increase in the
movement of potassium ions out of that neuron's cytoplasm would result in the .
CORRECT ANSWER hyperpolarization of the neuron
The operation of the sodium-potassium "pump" moves . CORRECT
ANSWER sodium ions out of the cell and potassium ions into the cell
ATP hydrolysis directly powers the movement of . CORRECT ANSWER Na+ out of cells
The "threshold" potential of a membrane is the . CORRECT
ANSWER minimum depolarization needed to operate the voltage-gated
sodium and
voltage-gated potassium channels
The membrane's permeability to sodium ions is at its maximum at . CORRECT ANSWER -50mV
The cell is not hyperpolarized; however, repolarization is in progress, as the sodium
channels are closing or closed, and many potassium channels have opened at .
CORRECT ANSWER the maximum mV of graph
If you experimentally increase the concentration of K+ inside a cell while maintaining
other ion concentrations as they were, what would happen to the cell's membrane
potential? CORRECT ANSWER The membrane potential would become less
negative.
If the activity of the sodium-potassium pump was completely stopped, what would
happen to the neuron's membrane potential? CORRECT ANSWER slow decrease of resting potential
Tetrodotoxin blocks voltage-gated sodium channels and ouabain blocks sodiumpotassium
,pumps. If you added both tetrodotoxin and ouabain to a solution containing
, neural tissue, what responses would you expect? CORRECT ANSWER
immediate loss of action potential with gradual loss of resting potential
Chum salmon (Oncorhynchus keta) are born in freshwater environments and then
migrate to the sea. Near the end of their lives, they return to the freshwater stream where
they were born to spawn. In freshwater, water constantly diffuses into the body and ions
are lost from the body. In salt water, body water diffuses out of the body and excess ions
are gained from the water. A salmon's gills have special cells to pump salt in or out of the
body to maintain homeostasis. In response to the salmon's moves between freshwater and
salt water, some cells in the gills are produced and others are destroyed. These changes
made in the cells of the gills during the lifetime of an individual salmon are an example
of which of the following?
A) evolution
B) trade-off
C) acclimatization
D) adaptation CORRECT ANSWER C) acclimatization
You observe two female fish of the same species breeding. One female lays 100 eggs
and the other female lays 1000 eggs. Which one of the following is LEAST likely given
the limits of fitness trade-offs?
A) The female laying 100 eggs breeds more often than the female laying 1000 eggs.
B) The female laying 100 eggs lives longer than the female laying 1000 eggs.
C) The eggs from the female laying 1000 eggs have larger yolks than the yolks of the
eggs from the female laying 100 eggs.
D) The female laying 1000 eggs is larger than the female laying 100 eggs. CORRECT ANSWER
C) The eggs from the female laying 1000 eggs have larger yolks than the yolks of the
eggs from the female laying 100 eggs
If you were to view a sample of animal tissue under a light microscope and notice an
WITH CORRECT ANSWERS 2025-2026
For a neuron with an initial membrane potential at -70 mV, an increase in the
movement of potassium ions out of that neuron's cytoplasm would result in the .
CORRECT ANSWER hyperpolarization of the neuron
The operation of the sodium-potassium "pump" moves . CORRECT
ANSWER sodium ions out of the cell and potassium ions into the cell
ATP hydrolysis directly powers the movement of . CORRECT ANSWER Na+ out of cells
The "threshold" potential of a membrane is the . CORRECT
ANSWER minimum depolarization needed to operate the voltage-gated
sodium and
voltage-gated potassium channels
The membrane's permeability to sodium ions is at its maximum at . CORRECT ANSWER -50mV
The cell is not hyperpolarized; however, repolarization is in progress, as the sodium
channels are closing or closed, and many potassium channels have opened at .
CORRECT ANSWER the maximum mV of graph
If you experimentally increase the concentration of K+ inside a cell while maintaining
other ion concentrations as they were, what would happen to the cell's membrane
potential? CORRECT ANSWER The membrane potential would become less
negative.
If the activity of the sodium-potassium pump was completely stopped, what would
happen to the neuron's membrane potential? CORRECT ANSWER slow decrease of resting potential
Tetrodotoxin blocks voltage-gated sodium channels and ouabain blocks sodiumpotassium
,pumps. If you added both tetrodotoxin and ouabain to a solution containing
, neural tissue, what responses would you expect? CORRECT ANSWER
immediate loss of action potential with gradual loss of resting potential
Chum salmon (Oncorhynchus keta) are born in freshwater environments and then
migrate to the sea. Near the end of their lives, they return to the freshwater stream where
they were born to spawn. In freshwater, water constantly diffuses into the body and ions
are lost from the body. In salt water, body water diffuses out of the body and excess ions
are gained from the water. A salmon's gills have special cells to pump salt in or out of the
body to maintain homeostasis. In response to the salmon's moves between freshwater and
salt water, some cells in the gills are produced and others are destroyed. These changes
made in the cells of the gills during the lifetime of an individual salmon are an example
of which of the following?
A) evolution
B) trade-off
C) acclimatization
D) adaptation CORRECT ANSWER C) acclimatization
You observe two female fish of the same species breeding. One female lays 100 eggs
and the other female lays 1000 eggs. Which one of the following is LEAST likely given
the limits of fitness trade-offs?
A) The female laying 100 eggs breeds more often than the female laying 1000 eggs.
B) The female laying 100 eggs lives longer than the female laying 1000 eggs.
C) The eggs from the female laying 1000 eggs have larger yolks than the yolks of the
eggs from the female laying 100 eggs.
D) The female laying 1000 eggs is larger than the female laying 100 eggs. CORRECT ANSWER
C) The eggs from the female laying 1000 eggs have larger yolks than the yolks of the
eggs from the female laying 100 eggs
If you were to view a sample of animal tissue under a light microscope and notice an
