Biology Forums - Study Force

1. Explain why increasing extracellular K+ reduces the net diffusion of K+ out of the neuron through the K+ leak channels.

2. Explain why increasing extracellular K+ causes the membrane potential to change to a less negative value.

3. Explain why a change in extracellular Na+ did not alter the membrane potential in the resting neuron.

4. Discuss the relative permeability of the membrane to Na+ and K+ in a resting neuron.

5. Discuss how changing in Na+ or K+ conductance would affect the resting membrane potential

2. Explain why increasing the extracellular K+ causes the membrane potential to change to a less negative value.

Potassium ions diffuse out across the membrane, leaving behind a net negative charge.

4. Discuss the relative permeability of the membrane to Na+ and to K+ in a resting neuron.

Membrane permeability to sodium is very low because there are only a few sodium leakage channels. Sodium ions do slowly diffuse inward, down their concentration gradient. Left unchecked, such inward leakage of sodium would eventually destroy the resting membrane potential. The small inward sodium leak and outward leak of potassium leak are offset by the sodium potassium pumps.

5. Discuss how a change in Na+ or K+ conductance would affect the resting membrane potential.

The resting period potential is a potential difference between the inside of the cell and the outside of the cell across the membrane. It depends on the resting permeability of the membrane to ions and on the intracellular and extracellular concentrations of those ions to which the membrane is permeable.


Hope this helps, I do not have the answers to any of the other one.

4.) K is more permeable during a resting neuron than Na.

1) By increasing the extracellular K+ there is efflux and also influx into the cell which increases the tendency of the cell to depolarize.

3)There are less leakage sodium channels that leakage potassium channels, and more of the potassium channels are open.