For protein three, the pi value is relatively basic. And for protein two, it's somewhere in the middle, so it's essentially neutral. So once again, in isoelectric focusing, a gel with a PH gradient is created. The two ends are connected to a voltage source, a battery, and the proteins are placed into our gel. Now, each protein will move due to the presence of an electric field as a result of that battery source. And so when they reach their pi value, the isoelectric point, they will stop moving because the net charge at the pi value of the protein is zero.