And as we know, nucleotides and amino acids are not the same type of molecules. So the question is, how exactly does the cell know what sequence of nucleotides corresponds to a sequence of amino acids? So once again, things become a bit more complicated when we synthesize proteins during the process of translation, which we'll discuss in much more detail in the next several lectures. So, in translation, the mRNA molecule, which itself is composed of nucleotides, is used as a template to synthesize our proteins that consist of amino acids. And here lies our problem. Nucleotides are different from amino acids, so we cannot use this complementary method.