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How does the membrane generate voltage to create a membrane potential?
Wiki User
∙ 12y ago
All cells have voltages across their plasma membranes. Voltage is electrical potential energy, which is a separation of opposite charges. The Cytoplasm of a cell is negative compared to extracellular fluid because of an unequal distribution of anions and cations which are on opposite sides of the membrane. The voltage created by that is is called the Membrane Potential. Which usually ranges from about -50 to -200 millivolts. The inside of the cell is negative compared to the outside, the why the they have the minus signs.
Wiki User
∙ 12y ago
Wiki User
∙ 11y agoIf you're pumping electrons across a membrane, you're leaving the side of the membrane you just took the electrons away from with a more positive charge. Themembrane side you pumped the electrons to now has a more negative charge. You have created a voltage gradient.
Wiki User
∙ 13y agoit is used for transmitting signals between different parts of a cell
Wiki User
∙ 13y agoVoltage would be measured by placing one electrode inside the membrane and another outside the membrane.
Wiki User
∙ 11y agoit is form the lipid bilayer
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What effect does potassium have on the resting potential of a cardiac cell?
Hyperkalemia is an increase in extracellular K. Driving force of an ion depends on two factors, voltage and concentration gradient. For K voltage gradient is pushing K into the cell but the concentration gradient is driving K out of the cell. However, the total driving force for K is out of the cell because the concentration gradient is that strong. When there is an increase in K on the outside, the driving force for K decreases.The equilibrium potential for K is -95mV. This means if K was freely permeable to the cell's membrane, it would reach equilibrium at -95mV. Another way to look at this is that efflux of K is the same as influx of K and the cell's new resting membrane potential would increase from a normal value of -70mV to -95mV. Note that I said it would increase even though the value became more negative. This is because the change in membrane potential has increased.Since the driving force of K has decreased, the equilibrium potential has also decreased. From a value of -95mV it is decreased to let's just say -80mV. Since a normal resting membrane potential is regularly -70mV, the decrease in equilibrium potential of K has decreased this resting membrane potential to say -60mV now. This is a depolarization of the cell.If this process happens quickly, it will depolarize the cell to the threshold value and you will have an action potential. However, if the hyperkalemia is severe, the cell will stay depolarized because the K equilibrium has decreased to a point where the cell cannot hyperpolarize back to threshold or resting membrane potential.If this process happens slowly, the inactivation gates of the sodium voltage-gated channels will automatically shut and the cell cannot depolarize even if it reaches threshold values. It must hyperpolarize back to resting membrane potential and the inactivation gates of the sodium voltage-gated channel will reopen.
How do molecules that are too large to cross the membrance enter into the cell?
If the large molecule won't pass through the membrane by diffusion, it might be dragged through the membrane by "endocytosis".
Where do motor neurons carry signals from?
The entire signal travels in the neuron by a graded potential which is created in the dendrites and the body (soma) of the neuron, then it reaches a spot of the neuron which is called the axon-hillock where the signal now for the first time has encountered "voltage-gated channels" and now can create an Action potential that can propagate through the terminus of the neuron which is the length of the axon.
IS nuclei are within the inner membrane of the mitochondria and increase its ability to create ATP?
No. The inner membrane contains many folds called cristae, which increase the surface area inside the organelle. The cristae increase the efficiency of the chemical reactions, allowing the mitochondria to create more ATP.
What are cell's power plant?
It is an organelle called the mitochondria
Why can't the potential barrier of a diode be used as a voltage source?
The potential barrier of a diode is caused by the movement of electrons to create holes. The electrons and holes create a potential barrier, but as this voltage will not supply current, it cannot be used as a voltage source.
What does a battery create between terminals?
Potential difference (voltage)
When ions move across a plasma membrane what will happen?
they create a flow of electrical currrent that can disturb the resting membrane potential.
Ions used to establish a resting potential?
Potassium and sodium determine the a cell's resting membrane potential. The equilibrium potential (the voltage where no ion would flow) for sodium is about +60 mV while that for potassium is usually around -80 mV, but because the resting cell membrane is approximately 75 times more permeable to potassium than to sodium, the resting potential is closer the the equilibrium potential of potassium. This is because potassium leak channels are always open while sodium come in through voltage gated or ligand gated channels.
What effect does potassium have on the resting potential of a cardiac cell?
Hyperkalemia is an increase in extracellular K. Driving force of an ion depends on two factors, voltage and concentration gradient. For K voltage gradient is pushing K into the cell but the concentration gradient is driving K out of the cell. However, the total driving force for K is out of the cell because the concentration gradient is that strong. When there is an increase in K on the outside, the driving force for K decreases.The equilibrium potential for K is -95mV. This means if K was freely permeable to the cell's membrane, it would reach equilibrium at -95mV. Another way to look at this is that efflux of K is the same as influx of K and the cell's new resting membrane potential would increase from a normal value of -70mV to -95mV. Note that I said it would increase even though the value became more negative. This is because the change in membrane potential has increased.Since the driving force of K has decreased, the equilibrium potential has also decreased. From a value of -95mV it is decreased to let's just say -80mV. Since a normal resting membrane potential is regularly -70mV, the decrease in equilibrium potential of K has decreased this resting membrane potential to say -60mV now. This is a depolarization of the cell.If this process happens quickly, it will depolarize the cell to the threshold value and you will have an action potential. However, if the hyperkalemia is severe, the cell will stay depolarized because the K equilibrium has decreased to a point where the cell cannot hyperpolarize back to threshold or resting membrane potential.If this process happens slowly, the inactivation gates of the sodium voltage-gated channels will automatically shut and the cell cannot depolarize even if it reaches threshold values. It must hyperpolarize back to resting membrane potential and the inactivation gates of the sodium voltage-gated channel will reopen.
How does an impulse travel from a presynaptic neuron to a postsynaptic neuron?
When the action potential reaches the button(axon terminal) of the presynaptic neuron the depolarization causes voltage gated calcium channels to open increasing intracellular calcium content. This causes synaptic vesicles to fuse to the membrane and release neurotransmitters that bind to the post synaptic neuron and create a chemical action potential.
Explain how cells generate resting potential?
Cells have ion transporters that create the electrical charge 3 Na+ out and 2 K+ in. This creates a charge difference across the cell membrane. It also expends ATP which has to be generated somewhere else by either oxidative metabolism or breaking down other compounds.
How is resting potential achieved?
The resting membrane potential difference between the inside and the outside of the cell is the result of selective permeability of the cell membrane and the active transport of ions into and out of the cell. Almost all cells have a potential difference, but some cells, neuron and heart muscle, also have voltage and chemically gated channels that allow for transient deviations from the resting potential.
How many things are needed to create a current?
A difference of potential (voltage) and a conductor connected to the voltage source will cause current flow. Not that you'd want to "short out" a voltage source with a piece of wire, but just the source of voltage and the conductor would permit current to flow. If you took a piece of wire and touched it to the terminals of a good battery, current would flow. It takes just those two things to create a current.
Is it possible to bypass the ignition coil temporarily in a 1993 Mazda b2600?
Ignition coils generate the voltage needed to create the spark for ignition of the fuel air mixture, without it the vehicle will not run.
How can two separate earthing conductors in one property be dangerous?
It is possible to create what are called ground loops where there can be a voltage potential between the grounds causing a shock hazard.
Is the ultimate receiver of information who may also generate or create information?
___________ is the ultimate receiver of information who may also generate or create information
