The Resting Potential Flashcards
What drives an ion from high to low concentration?
A concentration gradient
What is the value for resting potential?
-70 mv
What does an electrical gradient do?
Drives an ion towards an area of opposite charge
Are ion pumps or ion channels active?
Ion pumps (they move ions against their concentration gradient)
What is the membrane permeable to?
Freely permeable to potassium and only slightly permeable to sodium
What four factors contribute to the resting potential?
Hate intracellular protiens, the sodium/potassium pump, potassium ions and sodium ions
Hat do large negatively charged intracellular proteins do?
Stay in the cell and contribute to the negativity
What does the sodium/potassium pump do?
Moves 3NA ions out for every 2K ions in. It contributes to the cells negativity
What is an equilibrium potential (Eion)?
The electrical potential difference that exactly balances an ionic concentration gradient
What is the Nernst equation?
The voltage produced by a difference in concentration of a single ion across a membrane
Why is the Nernst equation not sufficient in calculate resting membrane potential?
Because it does not take the sodium ions into consideration
What equitation can be used to calculate the resting potential (Vm)?
The Goldman-Hodgkin-Katz equation
What is Vm-Eion?
The ionic driving force
