So we move three nucleotides this way, this uncharged tRNA moves into the e side, and our charged tRNA that contains the growing polypeptide chain moves from the a side and into the p side as shown in the diagram. And now our a side shown here is empty. And once our a side is empty, what happens is this entire process can repeat itself. Now, what exactly is the purpose of placing our uncharged tRNA into our easide? Well, the easide stands for the exit side. And once our uncharged tRNA molecule, the tRNA molecule that does not contain the amino acid, is moved into the east side, our ribosome then expels.