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.
Neuron Resting Potential-Resting Membrane Potential of the neuron. The voltage difference between the intracellular space and the extracellular space when a neuron is in its non-activated state, is the cells resting potential, which is around -- 70 mV. The resting potential is the electrical charge the cell has when it is resting and when it is not stimulated by any open ion channels.