Heme in hemoglobin is in the

Hemoglobin is found exclusively in red blood cells (RBC), where its main function is to transpo oxygen (O2) from the lungs to the capillaries of the tissues. Hemoglobin A, the major hemoglobin in adults, is composed of four polypeptide chains (two a chains and two b chains) held together by noncovalent interactions. Each chain (subunit) has stretches of a-helical structure and a hydrophobic heme-binding pocket similar to that described for myoglobin. Ref: LIPPINCOTT's Biochemistry 6th Edition page no. 27