A researcher conducts a voltage clamp experiment on a giant squid axon. She clamps a typical neuron at 0mV. Which graph represents the current changes she will observe.
a. A
b. B
c. C
d. D
e. E
Answer: a
Textbook
...
A researcher conducts a voltage clamp experiment on a giant squid axon. She clamps a typical neuron at 0mV. Which graph represents the current changes she will observe.
a. A
b. B
c. C
d. D
e. E
Answer: a
Textbook Reference: Two Types of Voltage-Dependent Ion Currents
Refer to the graph. A researcher conducts a voltage clamp experiment on a giant squid axon and collects the data shown in the graph. At what membrane potential was the cell clamped?
a. 0 mV
b. Sodium’s equilibrium potential
c. –65 mV
d. Potassium’s equilibrium potential
e. –110 mV
Answer: b
Textbook Reference: Two Types of Voltage-Dependent Ion Currents
Which observation is not evidence that helped to identify sodium as the early current of the action potential?
a. The current declined when there was decreased driving force on sodium fluxes.
b. The current disappeared near the Nernst potential for sodium.
c. The early current was blocked by tetrodotoxin.
d. The early current was unaffected by tetraethylammonium.
e. When the late current was blocked, the reversal potential of the inward current shifted to a negative membrane potential.
Answer: e
Textbook Reference: Two Types of Voltage-Dependent Ion Currents
Which treatment was shown to eliminate the early inward current in squid giant axons?
a. Removal of external sodium
b. Doubling of external sodium
c. Removal of external potassium
d. Doubling of external potassium
e. Removal of all external cations
Answer: a
Textbook Reference: Two Types of Voltage-Dependent Ion Currents
[Show More]
