Final answer:
We don't get shocked by the ions in our cells because the electrical signals they create are of low voltage and the ion concentrations inside and outside our cells are balanced, leading to a neutral charge. Our bodies are not capable of generating high voltages like some specialized animals such as the electric eel.
Step-by-step explanation:
The reason we do not get shocked by the ions used in our nerve cells is due to the way electrical signals are generated and transmitted in the body. Nerve impulses, much like electrical phenomena in nature, occur because of a difference in electrical charge across the plasma membrane of a neuron. The key is the ions, electrically charged atoms or molecules.
The concentration of ions inside and outside cells is carefully balanced, resulting in a net neutral charge. Nevertheless, a slight difference in charge at the membrane surface enables these cells to generate action potentials. In nerve cells, when a stimulus is detected, positive sodium (Na+) ions flow into the cell changing the membrane potential and initiating a nerve signal.
This process is at a molecular level with a very tiny voltage (about -70 mV across the cell membrane), which is far too small to be felt or cause a shock to our bodies. Unlike electric eels that can generate significant electric discharges, the voltage in human cells is not designed to add up and cause an electric shock.