Charges inside a cell Flashcards
Describe the charges inside and outside of the cell
Negatively charged inside
Positively charged outside
What is the charge inside a cell called?
Membrane potential
What is an electrical current
When charges flow from one area to another
What is the resting membrane potential?
-70mV
Where is K+ found?
Inside of a neuron
Where is NA+ found?
Outside of a neuron
What can a fixed anion not do and examples
Can’t cross cell membrane
Proteins and phosphate
What is a stimulus
Anything that will change the resting potential
What is a resting potential?
A high concentration of Na ions is outside of the cell membrane and a high concentration of K ion inside of cell
Negative ions inside of cell
More positive ions leave that enter so outside is a positive charge
When does the potential change?
Stimulation of a cell membrane
When the resting potential becomes more negative a membrane becomes depolarized Achieving threshold potential triggers action potential
When does action potential occur?
At threshold sodium channels open and Na diffuse into cell depolarizing the membrane
K channels open and K ions diffuse outward, repolarizing the membrane
A series of action potential occur along the axon
Where is the only part that Na and K can cross the cell membrane on the axon?
Nodes of Ranvier
