Membrane potentials in cells are determined primarily by three factors: 1) the concentration of ions on the inside and outside of the cell; 2) the permeability of the cell membrane to those ions (i.e., ion conductance) through specific ion channels; and 3) by the activity of electrogenic pumps (e.g., Na
+
/K
+
-ATPase and …
What contributes to the resting membrane potential quizlet?
The resting membrane potential is dependent upon two important factors: 1) differences in sodium and potassium concentrations across the membrane (electrochemical gradients) and 2) differences in sodium and potassium membrane permeability. – The concentration of K+ is higher inside than outside the cell.
Which three ions are most influential in creating the membrane potential in resting cells?
The greater the conductance of an ion, the more that ion will influence the membrane potential of the cell. The principal conductances responsible for establishing the resting membrane potential are that of
chloride, potassium, and sodium
.
What is the major role of the Na+- K+ pump in maintaining the resting membrane potential?
Sodium-potassium pumps
move two potassium ions inside the cell as three sodium ions are pumped out to maintain the negatively-charged membrane inside the cell
; this helps maintain the resting potential.
What contributes to the resting membrane potential?
The resting membrane potential is determined mainly by two factors:
the differences in ion concentration of the intracellular and extracellular fluids and
.
the relative permeabilities of the plasma membrane to different ion species
.
What factors affect the nerve resting potential?
A resting (non-signaling) neuron has a voltage across its membrane called the resting membrane potential, or simply the resting potential. The resting potential is determined by
concentration gradients of ions across the membrane and by membrane permeability to each type of ion.
What is the relationship between membrane potential and resting potential quizlet?
A) Membrane potential is the maximum charge difference that can be maintained by a neuron, and resting potential is
the minimum charge difference
.
What is the resting membrane potential and how is it maintained?
Resting membrane potentials are maintained by two different types of ion channels:
the sodium-potassium pump and the sodium and potassium leak channels
. Firstly, there is a higher concentration of thepotassium ions inside the cell in comparison to the outside of the cell.
What causes a nerve impulse to begin?
A nerve impulse is a sudden reversal of the electrical charge across the membrane of a resting neuron. … It begins
when the neuron receives a chemical signal from another cell
. The signal causes gates in sodium ion channels to open, allowing positive sodium ions to flow back into the cell.
What are the membrane potentials of living cells?
Differences in the concentrations of ions on opposite sides of a cellular membrane lead to a voltage called the membrane potential. Typical values of membrane potential are in the range
–40 mV to –70 mV
.
How does the Na +/ K+ ATPase maintain the membrane potential?
[3][4] The Na+K+-ATPase pump helps to maintain osmotic equilibrium and membrane potential in cells. The sodium and potassium move against the concentration gradients. The Na+ K+-ATPase pump maintains
the gradient of a higher concentration of sodium extracellularly and a higher level of potassium intracellularly
.
Does depolarization increase or decrease membrane potential?
Hyperpolarization and depolarization
Hyperpolarization is when the membrane potential becomes more negative at a particular spot on the neuron’s membrane, while depolarization is
when the membrane potential becomes less negative
(more positive).
What is the major role of the Na+-K+ pump in maintaining the resting membrane potential quizlet?
The Na+-K+ pump
actively transports both sodium and potassium ions across the membrane to compensate for their constant leakage
.
Why does activity of the Na +/ K+ pump affect the membrane potential?
Thus, the maintenance of a normal electrical function requires that the Na+/K+-pump maintain normal ionic concentrations within the cell. The activity of the Na+/K+-pump also influences the
membrane potential directly by generating an outward sodium current that is larger when the Na+/K+-pump activity is greater
.
What happens to resting membrane potential if sodium-potassium pump is blocked?
The sodium pump is by itself electrogenic, three Na+ out for every two K+ that it imports. So if you block all sodium pump activity in a cell, you would see an
immediate change in the membrane potential
because you remove a hyperpolarizing current, in other words, the membrane potential becomes less negative.
What happens when a resting neurons membrane Depolarizes?
What happens when a resting neuron’s membrane depolarizes? a.
There is a net diffusion of Na out of the cell.
… The neuron’s membrane voltage becomes more positive.
