Well, if we examine the protein sequence, the amino acid sequence of the protein will find a high density, a high number of serene and three ending residues. And it's these two residues that are basically needed to produce the old glycocytic bonds between the protein and the sugar molecule. So because mucins contain a high number of threeanine and steam residues, they are heavily glycosylated with the old glycositic linkages. Now, although most mucins are actually produced by the cells and released into the extracellular matrix, some of these mucins actually remain attached onto the cell membrane. And this is what is shown in this diagram. So we have the cell membrane, we have this hydrophobic section of the protein Children Brown and this is the rest of that protein.