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Flashcards in Membrane Potentials Deck (11):
1

Remember Na+ ___, K+ ___.

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

2

Define resting potential (Ef)

The difference/separation of charge across a plasma membrane while a cell is at rest

3

The four requirements for the genesis of a resting potential are

  • Presence of nondiffusible anions inside the cell (organelles)
  • Selective permeable membrane
  • Energy expenditure
  • Active transport ions

4

K+ in a cell at rests has an

  • _____ chemical gradient and
  • ______ electrical gradient

  • Outward chemical gradient
  • Inward electrical gradient

5

Na+ in a cell at rests has an

_____ chemical gradient and

______ electrical gradient

  • Inward chemical gradient
  • Inward electrical gradient

6

The depolarization phase of the action potential is _____.

and is caused by _____.

Resulting in _______ potential.

  • when the cell becomes less negative/more positive
  • Caused by sodium influx 
  • Decreasing potential

7

The repolarization phase of the action potential is _____.

and is caused by _____.

Resulting in _______ potential.

  • When the cell becomes more negative/less positive
  • caused by K+ flowing out
  • increasing potential

8

The hyperpolarization phase of the action potential is _____.

and is caused by _____.

Resulting in _______ potential.

  • more negative than the resting potential
  • Excess K+ flow out of the cell
  • Increased potential

9

The absolute refractory period is 

time interval during which no stimulus can elicit an action potential

10

The relative refractory period is 

a period of excitability during which a greater than normal strength of stimulus is required to elicit a cell response

11