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Questions and Answers
What is the purpose of calculating the equilibrium potential for different ions in a cell?
What is the purpose of calculating the equilibrium potential for different ions in a cell?
What is the primary driving force for the net diffusion of uncharged solutes across a cell membrane?
What is the primary driving force for the net diffusion of uncharged solutes across a cell membrane?
When dealing with charged solutes (ions) across a cell membrane, what two factors must be considered to determine the driving force for net diffusion?
When dealing with charged solutes (ions) across a cell membrane, what two factors must be considered to determine the driving force for net diffusion?
What is the formula for the driving force on a given ion across a cell membrane?
What is the formula for the driving force on a given ion across a cell membrane?
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Which of the following statements about the resting membrane potential and action potentials is correct?
Which of the following statements about the resting membrane potential and action potentials is correct?
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What is the driving force behind the generation of a diffusion potential?
What is the driving force behind the generation of a diffusion potential?
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If a membrane is impermeable to an ion, what happens to the generation of a diffusion potential?
If a membrane is impermeable to an ion, what happens to the generation of a diffusion potential?
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What factor determines the magnitude of a diffusion potential?
What factor determines the magnitude of a diffusion potential?
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How do diffusion potentials affect bulk ion concentrations in a solution?
How do diffusion potentials affect bulk ion concentrations in a solution?
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What happens to net diffusion of an ion when it reaches its equilibrium potential?
What happens to net diffusion of an ion when it reaches its equilibrium potential?
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What primarily establishes the resting membrane potential?
What primarily establishes the resting membrane potential?
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Which ions make the greatest contributions to the resting membrane potential?
Which ions make the greatest contributions to the resting membrane potential?
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What is the typical range of the resting membrane potential in most excitable cells?
What is the typical range of the resting membrane potential in most excitable cells?
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Why is the resting membrane potential close to the equilibrium potentials for K+ and Cl−?
Why is the resting membrane potential close to the equilibrium potentials for K+ and Cl−?
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How can the contribution of each ion to the membrane potential be evaluated?
How can the contribution of each ion to the membrane potential be evaluated?
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What is the net driving force on an ion when the actual membrane potential (Em) is more negative than the ion's equilibrium potential (EX)?
What is the net driving force on an ion when the actual membrane potential (Em) is more negative than the ion's equilibrium potential (EX)?
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What is the relationship between the actual membrane potential (Em) and the ion's equilibrium potential (EX) when the net driving force on the ion is zero?
What is the relationship between the actual membrane potential (Em) and the ion's equilibrium potential (EX) when the net driving force on the ion is zero?
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How does an ion 'think' the membrane potential is too positive or too negative?
How does an ion 'think' the membrane potential is too positive or too negative?
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What is the direction of ion movement when the net driving force on the ion is positive?
What is the direction of ion movement when the net driving force on the ion is positive?
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What is the purpose of the ion's 'desire' to bring the membrane potential towards its equilibrium potential?
What is the purpose of the ion's 'desire' to bring the membrane potential towards its equilibrium potential?
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What is the primary factor that determines the resting membrane potential of an excitable cell?
What is the primary factor that determines the resting membrane potential of an excitable cell?
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Which of the following statements accurately describes the process of depolarization?
Which of the following statements accurately describes the process of depolarization?
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According to the chord conductance equation, which of the following factors does NOT directly contribute to the membrane potential?
According to the chord conductance equation, which of the following factors does NOT directly contribute to the membrane potential?
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What is the primary function of action potentials in excitable cells?
What is the primary function of action potentials in excitable cells?
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Which of the following statements accurately describes the refractory period of an action potential?
Which of the following statements accurately describes the refractory period of an action potential?
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What happens when two solutions separated by a semipermeable membrane have the same effective osmotic pressure?
What happens when two solutions separated by a semipermeable membrane have the same effective osmotic pressure?
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How do ion channels discriminate among ions passing through them?
How do ion channels discriminate among ions passing through them?
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What does it mean when a solution is described as hypotonic?
What does it mean when a solution is described as hypotonic?
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When open, what do ion channels permit through them?
When open, what do ion channels permit through them?
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In terms of charges, what type of ions do channels lined with negative charges typically permit the passage of?
In terms of charges, what type of ions do channels lined with negative charges typically permit the passage of?
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How does a potential difference across a membrane affect the diffusion rate of charged solutes?
How does a potential difference across a membrane affect the diffusion rate of charged solutes?
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What is the main difference between simple diffusion and facilitated diffusion?
What is the main difference between simple diffusion and facilitated diffusion?
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What is a diffusion potential?
What is a diffusion potential?
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What happens when the concentration gradient and the charge effect are oriented in the same direction across a membrane?
What happens when the concentration gradient and the charge effect are oriented in the same direction across a membrane?
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Which of the following statements about facilitated diffusion is correct?
Which of the following statements about facilitated diffusion is correct?
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In the context of ion diffusion across cell membranes, what is meant by the term 'electrochemical potential gradient'?
In the context of ion diffusion across cell membranes, what is meant by the term 'electrochemical potential gradient'?
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Which of the following statements best describes the relationship between diffusion and the resting membrane potential in excitable cells?
Which of the following statements best describes the relationship between diffusion and the resting membrane potential in excitable cells?
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What is the primary driving force for the net diffusion of charged solutes across a cell membrane?
What is the primary driving force for the net diffusion of charged solutes across a cell membrane?
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In the context of ion diffusion across cell membranes, what is the significance of the membrane potential?
In the context of ion diffusion across cell membranes, what is the significance of the membrane potential?
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What is the primary role of facilitated diffusion in excitable cells?
What is the primary role of facilitated diffusion in excitable cells?
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