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.
*Each globin in hemoglobin contains one heme *Heme is a porphyrin molecule that contains iron *Each heme iron can bind one oxygen molecule (so each hemoglobin molecule can bind a maximum of 4 oxygen molecules *Iron gives RBC its red color.Each globin in hemoglobin contains one heme *Heme is a porphyrin molecule that contains iron *Each heme iron can bind one oxygen molecule (so each hemoglobin molecule can bind a maximum of 4 oxygen molecules *Iron gives RBC its red color.