Block 1 Lecture 3 Flashcards
What creates electrical voltage in cells
ion concentrations are different on the two sides of the plasma membrane
what does resting membrane potential depend on
ion gradients and ion channels
what is the sodium concentration inside and outside a cell
inside - 10 mM
outside- 120 mM
what is the potassium concentration inside and outside a cell
inside- 140
outside-2.5
what is the calcium concentration inside and outside a cell
inside- less than 10^-3
outside-2.0
what is the concentration of negatively charge protein and phosphate [A-] inside the cell
140
Where are K+ present
all cells
what does ATPase do?
develops and maintains steady state ion gradients for all cells
what charge do K+ ions create in the cytoplasm
negative
what charge do K+ ions create outside the cytoplasm
positive
what are the 2 opposing forces
chemical and electrical
what does the chemical force do
tends to push K+ out
what does the electrical force do
tends to pull K+ in
what is the ratio of chemical and electrical forces for K+ in most cells
chemical and electrical forces are nearly in balance
how does the inside negative electrical potential occur
K+ is directed outward of the cell due to the concentration gradient
