The charge on the cell membrane of the neuron was discussed in terms of positive ions and negative ions which are found in different concentrations outside and inside the axon membrane.
The change in permeability of the membrane due to a stimulus was shown to cause an influx of positive sodium ions into the cell with a corresponding change in charge. This was a change from a polarized nerve cell to a depolarized nerve cell. The wave of depolarization along the axon was defined as the nerve impulse. The secretion of neurotransmitter into the synapse by the axon terminal of one nerve cell and binding to a second nerve cell was introduced as the method by which the nerve transmission moves from one cell to another. A short video was looked at which showed this transmission.