This green group is the R atom. This carboxylic acid group contains a negative charge. This amino group contains a positive charge. And so, because we have these two separate and opposite charges, this is the dipolar form of the amino acid, the Zvitarion form. And because the majority of the cells and the solutions inside our body have a PH of around four, the majority of the amino acids exist in this Zvitor ion form. Now, the next question is what exactly happens to our amino acid, to the Zvitor ion, if we decrease the PH, make it more acidic, or increase the PH, make it more basic?