sarcolema-polarization Flashcards
sarcolemma is polarized when
the muscle fiber is relaxed
resting potential refers to
a difference in electrical charges between the outside and inside of cell
during polarization
outside of sarcolemma has positive charge inside has a negative charge
sodium ions are
more abundant outside of the cell
potassium ions are
more abundant inside the cell
sodium ions outside tend to
diffuse into cell and the sodium pump transfers them back out
potassium ions inside tend to
diffuse outside and the potassium pump returns them inside
both pumps are
active transport mechanisms which require ATP
muscle fibers use ATP to
maintain high sodium ions outside the cell and high potassium inside
the pumps therefore maintain polarization and relaxation until
nerve impulse stimulates change
