Now, one of the bond is formed between one of the amino acids of that polypeptide chain and this Is Shown In The Following Diagram. So if we take the heme group and we flip it this way, so if the heme group lies on the plane of the board and we take it and we flip it this way, then at the bottom portion of that hen group, we have an amino acid. More specifically, we have a HistoGene amino acid that is part of the protein either myoglobin or that hemoglobin that is bound onto that fe atom. So this purple circle is the fe atom. The green circle are the nitrogen atoms. The blue circles are the oxygen atoms.