At 1 AM, a researcher places a healthy squid giant axon in a bath of normal squid physiological extracellular saline and internally perfuses the axon with normal squid intracellular saline.
Its resting potential at 1:55 AM is -70 millivolts. For this question, ignore any possible effects due to the sodium-potassium pump. At 2 AM, the researcher replaces both the intracellular and the extracellular salines.
A. In the 2 AM intracellular perfusion saline, the concentration of potassium ion is decreased; in the 2 AM extracellular saline, the concentration of potassium ion is not changed. This will cause an increase in the Nernst equilibrium potential for potassium ion.
B. In the 2 AM intracellular perfusion saline, the concentration of potassium ion is decreased; in the 2 AM extracellular saline, the concentration of potassium ion is not changed. This will cause a decrease in the resting membrane voltage.
C. In the 2 AM extracellular saline, the concentration of potassium ion is increased; in the 2 AM intracellular perfusion saline, the concentration of potassium ion is not changed. This will cause a decrease in the Nernst equilibrium potential for potassium ion.