Definition: A portion of a line which starts at a point and goes off in a particular direction to infinity. Try this Adjust the ray below by dragging an orange dot and see how the ray AB behaves. Point A is the ray's endpoint.
Plant cell cross-section, showing the membrane. Animal cell cross-section, showing the membrane. Resting membrane potential is the difference in voltage of the fluids inside a cell and outside a cell, which is usually between -70 to -80 millivolts (mV). View slideshow of images above.
membrane potential the electric potential that exists on the two sides of a membrane or across the wall of a cell. resting potential (resting membrane potential) the difference in potential across the membrane of a cell when it is at rest, i.e., fully repolarized.In cardiac physiology this occurs during electrical diastole in pacemaker cells and continuously in nonpacemaker cells.embrane potential the electric potential that exists on the two sides of a membrane or across the wall of a cell. resting potential (resting membrane potential) the difference in potential across the membrane of a cell when it is at rest, i.e., fully repolarized.