Table of Contents
- 1 Why does increasing extracellular potassium cause the membrane potential to become less negative?
- 2 How does an increase in extracellular potassium affect the resting membrane potential?
- 3 What happens to membrane potential when extracellular K is increased and why?
- 4 Why does adding extracellular potassium elicit an action potential?
- 5 How would an increase of extracellular potassium affect the signaling capability of a neuron?
- 6 What effect does increasing extracellular K+ have on the net diffusion of K+ out of the cell?
- 7 Why does adding extracellular K+ depolarize membrane potential?
- 8 Why does extracellular K + decrease the membrane potential?
- 9 Why does the membrane potential change to a less negative value?
Why does increasing extracellular potassium cause the membrane potential to become less negative?
The Resting Membrane Potential Explain why increasing extracellular K+ reduces the net diffusion of K+ out of the neuron through the K+ leak channels. Increasing the extracellular potassium reduces the steepness of the concentration gradient and so less potassium diffuses out of the neuron.
How does an increase in extracellular potassium affect the resting membrane potential?
As previously discussed, increasing the extracellular potassium concentration results in a decrease in the resting membrane potential (that is, from −90 mV to −80 mV).
What happens to membrane potential when extracellular K is increased and why?
increase the membrane potential (hyperpolarize the cell) because the presence of extra potassium outside the cell will make the potassium equilibrium potential more negative.
What happens when extracellular potassium increases?
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 does increasing extracellular K+ have on the net diffusion of K+ out of the cell quizlet?
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.
Why does adding extracellular potassium elicit an action potential?
How would an increase of extracellular potassium affect the signaling capability of a neuron?
How will increasing extracellular potassium affect the signaling capability of a neuron? Increased extracellular potassium will depolarize the neuron and make it more likely to undergo an action potential. This occurs because the concentration gradient of potassium across the cell membrane is reduced.
What effect does increasing extracellular K+ have on the net diffusion of K+ out of the cell?
Action Potential
| Question | Answer |
|---|---|
| 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. |
How does increasing extracellular potassium affect the signaling capability of a neuron?
Why does increasing extracellular potassium reduces the net diffusion of potassium out of the neuron through the potassium leak channels?
Why does adding extracellular K+ depolarize membrane potential?
Membrane depolarization by elevated extracellular K+ concentration ([K+]o) causes rapid Na+ influx through voltage-sensitive Na+ channels into excitable cells. These results indicate that increased [K+]o does not open voltage-sensitive Na+ channels and may inhibit Na+ influx in astroglia.
Why does extracellular K + decrease the membrane potential?
Reduces the concentration gradient, so less K+ diffuses out of the neuron Explain why increasing extracellular K+ causes the membrane potential to change to a less negative value? Increasing extracellular K+ increases the positive charge outside the cell, making the inside of the cell (membrane potential) more negative.
Why does the membrane potential change to a less negative value?
Explain why increasing extracellular K+ causes the membrane potential to change to a less negative value? Increasing extracellular K+ increases the positive charge outside the cell, making the inside of the cell (membrane potential) more negative.
What is the effect of extracellular potassium levels?
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,…
What happens to the resting membrane potential when potassium is increased?
If there is an increase in potassium ions outside the cell (extracellular) then the resting membrane potential will become less negative. A nerve cell is also known as a neuron. The parts of the neuron are the dendrites, cell body, axon and axon terminals.