So this is our start site, this is exon number one, this is exxon number two and exxon number three, this is, let's say, intro number one, and this is intron number two. So we have introns exxon's a start site. Now, what about this segment and this segment here? So, together this entire region is known as the promoter. So just like operons in prokaryotic cells contain promoters, so do these Eukaryotic genes, but the promoters of Eukaryotic genes are much more complex. So we have different parts of the promoter, so the promoter can be broken down into the core promoter, which is basically shown in pink, this is our core promoter, and these remaining promoters are known as the upstream promoters.