So in this lecture, we're going to discuss the solid phase method of building proteins in the lab. So what exactly is the major point of the solid phase method? Well, there are two important points. Point number one is we begin at the amino acid that is at the terminal carboxyl end, and we take this amino acid and we attach it onto a solid surface. We basically anchor our amino acid on that solid surface and we continually attach amino acids one at a time. And that entire growing polypeptide chain is attached onto a solid surface.