Copyright ©Mark Nelson, 2002. All rights reserved.
Chapter 4: The Electrical Potential of a Resting Neuron
What you need to know
(exam questions will be a drawn from this subset of material)
What is the physical basis of the membrane potential?
(p. 91)
What charge carriers contribute?
(p. 91)
What three factors can induce an ion to cross the membrane?
(p. 91)
Which of these three factors are passive (no ATP); which
are active (require ATP)? (p. 92)
What conditions define the steady state for the
membrane potential? (p. 93)
When is a neuron's membrane potential in steady state?
(p. 93)
Which permeable ions have a HIGH intracellular concentration
relative to the extracellular concentration?
(p. 95)
Which permeable ions have a LOW intracellular concentration
relative to the extracellular concentration?
(p. 95)
What is the equilibrium potential for an ion?
(p. 97)
What is the Nernst equation? (p.
98)
Define the various symbols and terms in the Nernst equation.
(p. 99)
What is a typical equilibrium potential for K+, for Na+?
(p. 98-99)
If you increase the temperature of a neuron, do you change the magnitude
of the ionic equilibrium potentials? (p. 99)
If you double the temperature of a neuron from 18oC to
36 oC, do you double the ionic equilibrium potentials?
(p. 99)
When ions move across the cell membrane, do the intracellular and
extracellular concentrations change appreciably?
(p. 101)
If a neuron's resting potential is more (positive/negative) than an
ion's equilibrium potential, what will be the net effect?
(p. 101-102)
If the membrane of a hypothetical neuron were permeable only to K
+ ions, what would be the neuron's resting potential?
(p. 103)
Real neuronal membranes, at rest, are predominantly permeable to which
type of ion? (p. 103-104)
What is the Goldman equation? (p. 103-104)
What has a larger effect on the resting potential of a neuron, changing extracellular
[K+] or extracellular [Na+]?
(p. 104)
What is hyperkalemia? (Not in text)