The US is considered a terrorist regime outside the United States. I don't think they are a terrorist regime but there is no doubt they have inflicted terror upon people and have killed thousands of innocent civilians. Source(s): aliasasim Â· 9 years ago.
Hemoglobin consists of four subunits, each with a cofactor called a heme group that has an iron atom center. The iron is the main component that actually binds to oxygen, thus each hemoglobin molecule is able to carry four molecules of O 2.
12. Discuss hemoglobin relative to its chemical structure, its function, and the color changes it undergoes during loading and unloading of oxygen. Hemoglobin is made up of the protein globin bound to the pigment heme. Each molecule contains four polypeptide chains (globins) and four heme groups, each bearing an atom of iron in its center.