What effect does increasing extracellular K+ have on the net diffusion of K+ out of the cell? It decreases the net diffusion of K+ . Which way would Na+ move across the membrane if there were open Na+ channels? Na+ would diffuse into the cell.
What happens if you increase extracellular K+?
Increased extracellular potassium levels result in depolarization of the membrane potentials of cells due to the increase in the equilibrium potential of potassium. This depolarization opens some voltage-gated sodium channels, but also increases the inactivation at the same time.
What effect would increasing extracellular K+ have on membrane potential?
Increasing extracellular K+ increases the positive charge outside the cell, making the inside of the cell (membrane potential) more negative.
Why does increasing extracellular potassium depolarize neurons?
Because the resting neuronal membrane is highly permeable to K+, the membrane potential is sensitive to changes in the extracellular potassium concentration – increasing extracellular potassium depolarizes neurons.
How would an increase in extracellular K+ affect repolarization quizlet?
How would an increase in extracellular K+ affect repolarization? It will decrease the concentration gradient, causing less K+ to flow out of the cell during repolarization.
How does altering extracellular K+ alter the resting potential?
Resting membrane potential is negative because the negative charge inside the cell is greater than the positive charge outside the cell. Increasing extracellular K+ increases the positive charge outside the cell. This decreases the difference between the inside and outside of the cell.
What happens to the equilibrium potential of potassium if you increase the extracellular potassium concentration?
increase the membrane potential (hyperpolarize the cell) because the presence of extra potassium outside the cell will make the potassium equilibrium potential more negative.
Which would result from an increase in the extracellular concentration of K+ above normal?
13. Which would result from an increase in the extracellular concentration of K+ above normal? C. The potassium equilibrium potential of nerve cells would become more negative.
Does the resting membrane potential of a neuron change if the extracellular K+ is increased from 4 to 6 mM?
Does the resting membrane potential of a neuron change if the extracellular K+ is increased from 4 mM to 6 mM? B) YES. The resting membrane potential moves further away from threshold.
What would happen to the forces acting on K+ if you flooded the extracellular fluid with K+ ions?
What would happen in the AP if you flooded the extracellular space with K+? Excess extracellular K+ depolarizes the neuron (relative to the outside) so if it stays high then no more AP’s. A ten-fold rise in K+ eliminates the resting potential.
What effect would decreasing the concentration of extracellular potassium ions have on the membrane potential of a neuron?
if the extracellular concentration of potassium ions decreased, more potassium would leave the cell, and the electrical gradient across the membrane( the transmembrane potential) would increase. this condition is called hyperpolarization.
