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Questions and Answers
Oxygen ($O_2$) is freely diffusible across the plasma membrane.
Oxygen ($O_2$) is freely diffusible across the plasma membrane.
True
Charged ions can easily move across the hydrophobic interior of the plasma membrane.
Charged ions can easily move across the hydrophobic interior of the plasma membrane.
False
All cells possess a membrane potential due to the separation of opposite charges.
All cells possess a membrane potential due to the separation of opposite charges.
True
The plasma membrane is impermeable to all substances.
The plasma membrane is impermeable to all substances.
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Excitable cells can actively induce changes in their membrane potential.
Excitable cells can actively induce changes in their membrane potential.
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The major driving force for transport processes across membranes is the Na+-K pump.
The major driving force for transport processes across membranes is the Na+-K pump.
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Local anaesthetics enhance the activity of voltage-gated sodium channels.
Local anaesthetics enhance the activity of voltage-gated sodium channels.
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The Na+-Ca2+ exchanger is an example of an exchanger that transports calcium ions out of the cell.
The Na+-Ca2+ exchanger is an example of an exchanger that transports calcium ions out of the cell.
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Voltage-gated channels are always open and allow ions to flow freely.
Voltage-gated channels are always open and allow ions to flow freely.
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Ca2+-channel blockers are commonly used as antihypertensive drugs.
Ca2+-channel blockers are commonly used as antihypertensive drugs.
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The sodium-potassium ATPase transports three Na+ ions out of the cell and two K+ ions into the cell.
The sodium-potassium ATPase transports three Na+ ions out of the cell and two K+ ions into the cell.
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Two Ca2+ ions are transported into the cell by the sodium-potassium ATPase.
Two Ca2+ ions are transported into the cell by the sodium-potassium ATPase.
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Depolarization results in a more negative membrane potential.
Depolarization results in a more negative membrane potential.
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Hyperpolarization makes the resting membrane potential more negative.
Hyperpolarization makes the resting membrane potential more negative.
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The primary function of the sodium-potassium ATPase is to establish ionic gradients across the cell membrane.
The primary function of the sodium-potassium ATPase is to establish ionic gradients across the cell membrane.
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The sodium-potassium ATPase transports three Cl- ions out of the cell and two Na+ ions into the cell.
The sodium-potassium ATPase transports three Cl- ions out of the cell and two Na+ ions into the cell.
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Repolarization is the process that restores the membrane potential after depolarization.
Repolarization is the process that restores the membrane potential after depolarization.
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Cotransporters primarily use the chemical gradient of K+ to transport substances into the cell.
Cotransporters primarily use the chemical gradient of K+ to transport substances into the cell.
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The resting membrane potential is -70 mV.
The resting membrane potential is -70 mV.
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K+ ions leak into the cell because of the chemical gradient.
K+ ions leak into the cell because of the chemical gradient.
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A- ions can freely pass through the plasma membrane.
A- ions can freely pass through the plasma membrane.
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Phosphatidylinositol (PIP2) and phosphatidylserine (PS) contribute positive charge to the inner membrane.
Phosphatidylinositol (PIP2) and phosphatidylserine (PS) contribute positive charge to the inner membrane.
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The Nernst equation is used to calculate the equilibrium potential for an ion.
The Nernst equation is used to calculate the equilibrium potential for an ion.
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The concentration gradient for K+ acts as a driving force for its movement into the cell.
The concentration gradient for K+ acts as a driving force for its movement into the cell.
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At equilibrium, the electrical and chemical forces for K+ balance each other.
At equilibrium, the electrical and chemical forces for K+ balance each other.
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The intracellular concentration of K+ is lower than that in the extracellular fluid.
The intracellular concentration of K+ is lower than that in the extracellular fluid.
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The Nernst equilibrium shows that K+ diffusion is driven by both chemical and electrical gradients.
The Nernst equilibrium shows that K+ diffusion is driven by both chemical and electrical gradients.
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The constant 61 in the Nernst equation is related to the gas constant and temperature.
The constant 61 in the Nernst equation is related to the gas constant and temperature.
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A membrane potential occurs when there is a difference in charge across the membrane.
A membrane potential occurs when there is a difference in charge across the membrane.
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The intracellular environment is always positively charged compared to the extracellular environment.
The intracellular environment is always positively charged compared to the extracellular environment.
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Electrically neutral fluids can still have a membrane potential.
Electrically neutral fluids can still have a membrane potential.
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Separation of charges across the membrane is responsible for the membrane potential.
Separation of charges across the membrane is responsible for the membrane potential.
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The resting membrane potential of a neuron is approximately -70 mV.
The resting membrane potential of a neuron is approximately -70 mV.
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An absence of a membrane potential indicates a charge difference is present across the membrane.
An absence of a membrane potential indicates a charge difference is present across the membrane.
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Charge separation across the membrane does not affect the potential magnitude.
Charge separation across the membrane does not affect the potential magnitude.
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Positive charges can accumulate inside the cell to create a membrane potential.
Positive charges can accumulate inside the cell to create a membrane potential.
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The plasma membrane allows the free movement of charged ions due to its hydrophilic nature.
The plasma membrane allows the free movement of charged ions due to its hydrophilic nature.
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Membrane potential is generated by the separation of positively and negatively charged ions across the membrane.
Membrane potential is generated by the separation of positively and negatively charged ions across the membrane.
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Excitable cells utilize changes in membrane potential for conducting electrical signals.
Excitable cells utilize changes in membrane potential for conducting electrical signals.
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All cells lack a membrane potential due to the uniform distribution of charges.
All cells lack a membrane potential due to the uniform distribution of charges.
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Lipid-soluble molecules can freely diffuse across the plasma membrane.
Lipid-soluble molecules can freely diffuse across the plasma membrane.
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The Na+/K+ ATPase transports 2 Na+ ions into the cell for every 3 K+ ions pumped out.
The Na+/K+ ATPase transports 2 Na+ ions into the cell for every 3 K+ ions pumped out.
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The primary reason for the negative resting membrane potential is the diffusion of K+ out of the cell.
The primary reason for the negative resting membrane potential is the diffusion of K+ out of the cell.
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Large protein anions (A-) are more concentrated in the extracellular fluid than in the intracellular fluid.
Large protein anions (A-) are more concentrated in the extracellular fluid than in the intracellular fluid.
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The sodium-potassium pump uses ATP to establish concentration gradients for both Na+ and K+ across the plasma membrane.
The sodium-potassium pump uses ATP to establish concentration gradients for both Na+ and K+ across the plasma membrane.
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The resting membrane potential of a neuron is approximately +70 mV.
The resting membrane potential of a neuron is approximately +70 mV.
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The sodium-potassium ATPase transports three Na+ ions into the cell and two K+ ions out of the cell.
The sodium-potassium ATPase transports three Na+ ions into the cell and two K+ ions out of the cell.
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The equilibrium potential for Na+ is positive, usually around +60 mV.
The equilibrium potential for Na+ is positive, usually around +60 mV.
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K+ ions are primarily concentrated outside of the cell.
K+ ions are primarily concentrated outside of the cell.
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The Nernst equation can be used to determine the equilibrium potential for any ion based on its concentration gradient.
The Nernst equation can be used to determine the equilibrium potential for any ion based on its concentration gradient.
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Electrical gradients do not influence ion movement across the plasma membrane.
Electrical gradients do not influence ion movement across the plasma membrane.
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When a sodium channel opens, the membrane potential becomes more negative.
When a sodium channel opens, the membrane potential becomes more negative.
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The resting membrane potential of a typical neuron is approximately -70 mV.
The resting membrane potential of a typical neuron is approximately -70 mV.
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The presence of a membrane potential indicates that there is a charge difference across the plasma membrane.
The presence of a membrane potential indicates that there is a charge difference across the plasma membrane.
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In the resting membrane potential, the intracellular environment is more positive than the extracellular environment.
In the resting membrane potential, the intracellular environment is more positive than the extracellular environment.
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Na+ ions are highly permeable due to many leak channels in the plasma membrane.
Na+ ions are highly permeable due to many leak channels in the plasma membrane.
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Electrically neutral fluids can exhibit a membrane potential if there is charge separation at the membrane.
Electrically neutral fluids can exhibit a membrane potential if there is charge separation at the membrane.
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A neuron at rest experiences a membrane potential of about 0 mV.
A neuron at rest experiences a membrane potential of about 0 mV.
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Charge separation across the membrane is not essential for establishing a membrane potential.
Charge separation across the membrane is not essential for establishing a membrane potential.
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The potential magnitude of a membrane depends on the degree of charge separation.
The potential magnitude of a membrane depends on the degree of charge separation.
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The intracellular concentration of Na+ is higher than that in the extracellular environment.
The intracellular concentration of Na+ is higher than that in the extracellular environment.
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In the absence of a membrane potential, oppositely charged ions are evenly distributed across the membrane.
In the absence of a membrane potential, oppositely charged ions are evenly distributed across the membrane.
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K+ ions primarily leak into the cell due to a large concentration gradient.
K+ ions primarily leak into the cell due to a large concentration gradient.
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The resting membrane potential of a cell is approximately -70 mV.
The resting membrane potential of a cell is approximately -70 mV.
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A- ions can pass freely through the plasma membrane.
A- ions can pass freely through the plasma membrane.
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Phosphatidylserine (PS) contributes positively charged residues to the inner membrane potential.
Phosphatidylserine (PS) contributes positively charged residues to the inner membrane potential.
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The Nernst equation is utilized to find the equilibrium potential for an ion.
The Nernst equation is utilized to find the equilibrium potential for an ion.
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At equilibrium, there is a net movement of K+ ions across the membrane.
At equilibrium, there is a net movement of K+ ions across the membrane.
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The electrical gradient for K+ ions draws them into the cell.
The electrical gradient for K+ ions draws them into the cell.
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Inside the cell, the concentration of K+ is significantly higher than that in the extracellular fluid.
Inside the cell, the concentration of K+ is significantly higher than that in the extracellular fluid.
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The residual negative charge inside the cell is due to the presence of K+ ions.
The residual negative charge inside the cell is due to the presence of K+ ions.
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The sodium-potassium ATPase actively maintains the higher concentration of Na+ ions inside the cell compared to the extracellular space.
The sodium-potassium ATPase actively maintains the higher concentration of Na+ ions inside the cell compared to the extracellular space.
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The hydrophobic interior of the plasma membrane allows charged ions to freely pass through.
The hydrophobic interior of the plasma membrane allows charged ions to freely pass through.
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All cells exhibit a membrane potential due to the presence of cations outside and anions inside the cell.
All cells exhibit a membrane potential due to the presence of cations outside and anions inside the cell.
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Membrane potential is influenced by both the concentration gradient and the permeability of the membrane to specific ions.
Membrane potential is influenced by both the concentration gradient and the permeability of the membrane to specific ions.
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The difference in electrical potentials across the membrane is critical for the excitability of nerve and muscle cells.
The difference in electrical potentials across the membrane is critical for the excitability of nerve and muscle cells.
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A lack of membrane potential suggests that a cell has equal distribution of cations and anions on both sides of its membrane.
A lack of membrane potential suggests that a cell has equal distribution of cations and anions on both sides of its membrane.
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The plasma membrane has a width of approximately 3 – 10 nm.
The plasma membrane has a width of approximately 3 – 10 nm.
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Endocytosis includes only the process of phagocytosis.
Endocytosis includes only the process of phagocytosis.
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Communication between cells is one of the functions of the plasma membrane.
Communication between cells is one of the functions of the plasma membrane.
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Integral membrane proteins can only be found on the exterior surface of the plasma membrane.
Integral membrane proteins can only be found on the exterior surface of the plasma membrane.
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Lipid-soluble molecules cannot diffuse across the plasma membrane.
Lipid-soluble molecules cannot diffuse across the plasma membrane.
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The hydrophilic heads of phospholipids face the extracellular and intracellular environments.
The hydrophilic heads of phospholipids face the extracellular and intracellular environments.
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The function of the sodium-potassium ATPase is solely to transport sodium ions into the cell.
The function of the sodium-potassium ATPase is solely to transport sodium ions into the cell.
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Depolarization increases the membrane potential towards a more positive value.
Depolarization increases the membrane potential towards a more positive value.
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The Na+/K+ ATPase transports 3 K+ ions out of the cell for every 2 Na+ ions it transports in.
The Na+/K+ ATPase transports 3 K+ ions out of the cell for every 2 Na+ ions it transports in.
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Large protein anions (A-) are more concentrated in the intracellular fluid than in the extracellular fluid.
Large protein anions (A-) are more concentrated in the intracellular fluid than in the extracellular fluid.
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The resting membrane potential of a neuron is primarily due to the influx of Na+ ions.
The resting membrane potential of a neuron is primarily due to the influx of Na+ ions.
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The sodium-potassium ATPase establishes concentration gradients for both Na+ and K+ by using energy derived from glucose.
The sodium-potassium ATPase establishes concentration gradients for both Na+ and K+ by using energy derived from glucose.
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The cell membrane is selectively permeable, allowing more K+ ions to diffuse out than Na+ ions to diffuse in.
The cell membrane is selectively permeable, allowing more K+ ions to diffuse out than Na+ ions to diffuse in.
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The sodium-potassium ATPase transports three Na+ ions into the cell and two K+ ions out of the cell.
The sodium-potassium ATPase transports three Na+ ions into the cell and two K+ ions out of the cell.
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The equilibrium potential for Na+ is negative, usually around -60 mV.
The equilibrium potential for Na+ is negative, usually around -60 mV.
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When the membrane becomes more permeable to Na+, the membrane potential will shift from negative to positive.
When the membrane becomes more permeable to Na+, the membrane potential will shift from negative to positive.
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The Nernst equation incorporates the gas constant, absolute temperature, and the valence of ions to determine the equilibrium potential.
The Nernst equation incorporates the gas constant, absolute temperature, and the valence of ions to determine the equilibrium potential.
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The concentration of K+ is higher outside the cell compared to inside the cell.
The concentration of K+ is higher outside the cell compared to inside the cell.
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The resting membrane potential is primarily determined by the permeability of the membrane to Na+ ions.
The resting membrane potential is primarily determined by the permeability of the membrane to Na+ ions.
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The electrochemical gradient for Na+ encourages its movement into the cell despite low permeability.
The electrochemical gradient for Na+ encourages its movement into the cell despite low permeability.
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The constant 61 in the Nernst equation applies specifically when calculating the equilibrium potential of ions with a valence of +2.
The constant 61 in the Nernst equation applies specifically when calculating the equilibrium potential of ions with a valence of +2.
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The residual negative charge inside the cell acts as an electrical driving force drawing K+ ions into the cell.
The residual negative charge inside the cell acts as an electrical driving force drawing K+ ions into the cell.
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The Nernst equation consistently predicts an equilibrium potential for K+ that is negative under physiological conditions.
The Nernst equation consistently predicts an equilibrium potential for K+ that is negative under physiological conditions.
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Phosphatidylserine (PS) contributes a positive charge to the inner portion of the plasma membrane.
Phosphatidylserine (PS) contributes a positive charge to the inner portion of the plasma membrane.
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At equilibrium, there is a net transport of K+ ions into the cell.
At equilibrium, there is a net transport of K+ ions into the cell.
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The concentration of Na+ in the extracellular fluid (ECF) is lower than in the intracellular fluid (ICF).
The concentration of Na+ in the extracellular fluid (ECF) is lower than in the intracellular fluid (ICF).
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K+ ions leak into the cell primarily due to the large concentration gradient that exists for K+.
K+ ions leak into the cell primarily due to the large concentration gradient that exists for K+.
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The equilibrium potential for K+ can be calculated using the formula E = + 61 x log(Ci/Co).
The equilibrium potential for K+ can be calculated using the formula E = + 61 x log(Ci/Co).
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Large protein anions (A-) can easily diffuse across the plasma membrane.
Large protein anions (A-) can easily diffuse across the plasma membrane.
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A- ions are concentrated in the intracellular fluid, contributing to a negative membrane potential.
A- ions are concentrated in the intracellular fluid, contributing to a negative membrane potential.
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K+ ions have a permeability of only 1 in the context of the membrane potential.
K+ ions have a permeability of only 1 in the context of the membrane potential.
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Study Notes
Membrane Permeability
- Lipid soluble and small uncharged molecules can move freely due to the concentration gradient across the cell membrane.
- Charged molecules (ions) and water-soluble molecules cannot move freely across the cell membrane due to the hydrophobic interior of the plasma membrane.
- The cell membrane is selectively permeable, allowing some molecules to pass through while blocking others.
Membrane Potential
- The separation of opposite charges across a membrane generates an electrical potential.
- All cells possess a membrane potential.
- Excitable cells, such as nerve and muscle cells, can actively induce changes in membrane potential, facilitating electrical signaling.
- Membrane potential is used to transport substances across membranes.
- The magnitude of the membrane potential relies on the difference of charge separation across the membrane.
Resting Membrane Potential (RMP)
- The cell membrane is more negative on the inside than on the outside at RMP.
- The RMP of a neuron is approximately -70 mV.
- The RMP is maintained by the relative permeability of the membrane to various ions, notably Potassium (K+).
- At rest, the membrane is more permeable to K+, allowing K+ to diffuse out of the cell down its concentration gradient.
- The movement of K+ out of the cell contributes to the negative charge on the inside of the membrane.
- The presence of negatively charged molecules (A-), which cannot cross the membrane, inside the cell further enhances the negative potential.
Nernst Equilibrium Potential
- There is a chemical gradient driving the diffusion of K+ out of the cell.
- The negative charge inside the cell creates an electrical gradient, pulling K+ back into the cell.
- Nernst Equilibrium refers to the state where the electrical and chemical gradients balance each other, resulting in no net movement of K+.
Sodium-Potassium Pump
- The sodium-potassium pump is an enzyme embedded in the cell membrane, actively transporting ions across the membrane.
- The pump moves three sodium ions (Na+) out of the cell and two potassium ions (K+) into the cell, contributing to the membrane potential and maintaining ionic gradients.
Membrane Potential Changes
- Depolarization: Membrane potential becomes more positive.
- Hyperpolarization: Membrane potential becomes more negative.
- Repolarization: The membrane potential returns to its resting state.
Ion Channels
- Leak channels: Continuously allow the passage of ions, like the K+ leak channel, allowing diffusion of potassium ions across the membrane.
- Voltage-gated channels: Regulated by changes in membrane potential, like the voltage-gated sodium channel (VGSC).
- Ligand-gated channels: Open upon binding to specific molecules, like neurotransmitters, such as the acetylcholine receptor.
Drugs Affecting Ion Channels
- Local anaesthetics, like Xylocaine/Lidocaine, block voltage-gated sodium channels, reducing neuronal excitability.
- Ca2+-channel blockers, like nifedipine, block calcium channels, affecting muscle contraction and vascular tone.
Cell Membrane
- The cell membrane is selectively permeable, allowing certain substances to pass through while blocking others.
- Lipid-soluble and small uncharged molecules, such as oxygen (O2), can freely diffuse across the membrane, driven by a concentration gradient.
- Charged molecules (ions) and water-soluble molecules cannot move freely across the membrane due to the hydrophobic interior.
Membrane Potential
- Separation of opposite charges across the membrane creates an electrical difference known as the membrane potential.
- All cells have a membrane potential, which is crucial for the electrical excitability of nerve and muscle cells, and for transporting substances.
- The magnitude of the membrane potential depends on the degree of charge separation across the membrane.
- It is maintained by an uneven distribution of ions across the membrane, primarily due to the difference in K+ and Na+ concentrations.
Resting Membrane Potential (RMP)
- The cell membrane is more negative on the inside compared to the outside, with a typical value of -70 mV in neurons.
- This is due to:
- Unequal distribution of K+, Na+, and negatively charged proteins (A-) inside and outside the cell.
- The high permeability of the membrane to K+, allowing it to leak out down its concentration gradient.
- The Na+/K+ ATPase pump actively transports ions across the membrane, contributing to the RMP by pumping out 3 Na+ ions for every 2 K+ ions pumped in.
- The diffusion of K+ out of the cell down its concentration gradient is the primary factor responsible for the negative RMP.
Ion Distribution and RMP
- The concentration of K+ is much higher inside the cell (150 mM) compared to outside (5 mM).
- Na+ concentration is higher outside (150 mM) than inside (15 mM).
- Large negatively charged proteins (A-) are predominantly found inside the cell (65 mM).
The Na+/K+ ATPase Pump
- This transmembrane enzyme utilizes ATP to transport Na+ ions out and K+ ions into the cell.
- It maintains the concentration gradients for both ions, which are crucial for the establishment and maintenance of the RMP.
Nernst Equilibrium
- The chemical gradient for K+ drives its outward diffusion, while the negative charge inside the cell attracts K+ back in.
- At equilibrium, the electrical and chemical forces balance, resulting in no net movement of K+ ions.
Nernst Equation
- This equation calculates the equilibrium potential for an ion, taking into consideration its concentration gradient across the membrane.
- The equilibrium potential for K+ is close to -90 mV, indicating that the RMP is mainly determined by K+ permeability.
Sodium (Na+) Contribution to RMP
- Na+ has a higher concentration outside the cell, and both its concentration gradient and electrical gradient would drive it into the cell.
- However, the membrane is relatively impermeable to Na+ due to a limited number of leak channels.
Importance of K+ Equilibrium Potential
- The RMP is closely related to the equilibrium potential of K+.
- If the membrane becomes permeable to another ion, it will move towards its equilibrium potential, leading to a change in the membrane potential.
Sodium-potassium ATPase Function
- The Na+/K+ ATPase pump is essential for maintaining the ionic gradients across the cell membrane, which are crucial for various cellular processes.
- It transports 3 Na+ ions out of the cell and 2 K+ ions into the cell.
Cell Membrane
- Composed of a fluid lipid-protein bilayer, 3-10nm thick
- Acts as a structural barrier for cells
-
Functions:
- Encloses the cell
- Controls the movement of substances in and out of the cell
- Maintains different concentrations of molecules inside and outside the cell, including nutrients and waste products
- Contributes to cell fluidity
- Enables communication between cells
- Mediates responses to external stimuli
- Protein components:
- Integral/transmembrane proteins: embedded within the membrane
- Extrinsic/peripheral proteins: associated with the membrane surface
Transport Across Membranes
-
Passive transport:
- Diffusion: movement of molecules down their concentration gradient (e.g., O2, CO2, lipid-soluble substances)
-
Active transport:
- Protein-mediated: mediated by channel or carrier proteins
- Endocytosis: engulfing of extracellular material by the cell membrane
- Phagocytosis: engulfment of large particles
- Pinocytosis: engulfment of fluids and small particles
- Endocytosis: engulfing of extracellular material by the cell membrane
- Exocytosis: release of cellular material to extracellular space
- Protein-mediated: mediated by channel or carrier proteins
Membrane Potential
- Definition: The electrical difference across the cell membrane due to a separation of charges
- Origin: Unequal distribution of cations (+) and anions (-) across the plasma membrane (PM)
-
Importance:
- All cells have a membrane potential, and it is essential for various cellular functions
- Serves as a basis for electrical excitability in nerve and muscle cells
- Plays a role in the transport of substances across the membrane
Resting Membrane Potential (RMP)
- Definition: The electrical potential difference across the cell membrane when the cell is at rest
- Characteristics: The inside of the cell is typically more negative than the outside, typically around -70mV in neurons
-
Contributing factors:
- Unequal distribution of ions across the membrane:
- High potassium (K+) concentration inside the cell
- High sodium (Na+) concentration outside the cell
- A- (large protein anions) primarily inside the cell
- Selective permeability of the PM to K+ ions:
- More K+ leak channels allow for greater potassium diffusion out of the cell
- Unequal distribution of ions across the membrane:
Ion Distribution & RMP
| Ion | ECF (mM) | ICF (mM) |
|---|---|---|
| K+ | 5 | 150 |
| Na+ | 150 | 15 |
| A- | 0 | 65 |
Na+/K+ ATPase (Pump)
- Function: Maintains the ionic gradients across the PM by transporting Na+ out of the cell and K+ into the cell
- Ratio: 3 Na+ ions out for every 2 K+ ions in
- Energy: Requires energy in the form of ATP
- Impact: Establishes and maintains the concentration gradients of Na+ and K+ across the cell membrane
Nernst Equation
- Purpose: Calculates the equilibrium potential (E) for an ion, which is the potential difference across the membrane when the electrical and chemical forces for that ion are balanced
-
Formula: E = 61 x log (Co/Ci), where:
- E is the equilibrium potential in mV
- 61 is a constant reflecting the gas constant, absolute temperature, ion valence, and Faraday constant
- Co is the concentration of the ion outside the cell
- Ci is the concentration of the ion inside the cell
Equilibrium Potential for K+ (EK+)
- Calculation: EK+ = 61 x log (5mM/150mM) ≈ -90mV
Equilibrium Potential for Na+ (ENa+)
- Calculation: ENa+ = 61 x log (150mM/15mM) ≈ 60mV
Importance of K+ Equilibrium Potential
- The resting membrane potential of a cell typically sits close to the equilibrium potential for potassium
- Changes in membrane permeability to other ions can shift the membrane potential toward the equilibrium potential for that ion
Role of Sodium-Potassium ATPase
- Crucial for maintaining the ionic gradients across the cell membrane
- Essential for maintaining the resting membrane potential and enabling nerve and muscle cell function.
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Description
Explore the complexities of membrane permeability and membrane potential with this quiz. Understand how the selective permeability of the cell membrane affects molecule transport and the role of membrane potential in cell signaling. Test your knowledge on key concepts such as resting membrane potential and the behavior of excitable cells.
