Answer to Question #59100 in Cell Biology for Tracy Guido

Question

23.
What is an equilibrium potential
the potential across a membrane at which flow of a specific ion into the cell equals the flow out of the cell
the difference in positive and negative charge across the membrane of an unstimulated, resting cell
the transmembrane potential at which there is no movement of any individual ions into or out of the cell



26
Action potentials in neurons involve opening and closing of voltage-gated Na and K ion channels. Place the events of an action potential in order, starting and ending with a cell at its resting membrane potential.
1. K rushes out the cell, causing repolarization 2. a graded potential brings the membrane to threshold potential. 3. K channels fully open, and Na channel inactivation gates close. 4. Na rushes into cell, causing membrane depolarization. 5. Fast Na and slow K channels are activated. 6. K channels close slowly resulting in hyperpolarization Na channel gate reset

Answer 1

23. the difference in positive and negative charge across the membrane of an unstimulated, resting cell

26. 4. Na rushes into cell, causing membrane depolarization.
3. K channels fully open, and Na channel inactivation gates close.
1. K rushes out the cell, causing repolarization.
6. K channels close slowly resulting in hyperpolarization Na channel gate reset.
5. Fast Na and slow K channels are activated.
2. a graded potential brings the membrane to threshold potential.