This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
HaemaincyctochromecoxidasePDBOCRDballsB. Ballandstick model of the haem molecule as found in the crystal structure of bovine heart cytochrome oxidase Histidine residues coordinating the iron atom have been omitted for clarity Colour code Carbon greyblack Hydrogen white Nitrogen blue Oxygen red Iron Fe bluegrey Structure by Xray crystallography