Final answer:
Depolarization of a neuron cell membrane will shift the membrane potential toward 0 mV, due to the influx of Na+ ions and the consequent reduction in negative charge inside the neuron.
Step-by-step explanation:
Depolarization of a neuron cell membrane will shift the membrane potential toward 0 mV. During depolarization, the membrane potential becomes less negative (closer to zero), moving from a resting potential of approximately -70 mV up towards positive values. The membrane potential changes due to the influx of sodium (Na+) ions when stimulated, leading to a potential that can reach up to +30 mV, which signifies the peak of an action potential. After this peak is reached, repolarization occurs as potassium (K+) ions exit the cell, bringing the membrane potential back down to its resting state.
The question relates to the phases of an action potential in neurons – a foundational concept in neurobiology. Understanding these changes in electric potential is crucial for grasping how electrical signals travel through the nervous system. Normally, approximately 25% of the cell's energy expenditure is dedicated to maintaining the resting membrane potential, illustrating the significance of these biophysical processes.