MICROANATOMY

Detailed explanation-1: -The hemoglobin molecule has four binding sites for oxygen molecules: the iron atoms in the four heme groups. Thus, each Hb tetramer can bind four oxygen molecules. From the molecular weight of Hb, one can calculate that 1 g of Hb can combine with 1.39 ml of oxygen.

Detailed explanation-2: -Iron is essential in making hemoglobin, a protein in red blood cells. These red blood cells help carry oxygen throughout your body. Six percent of iron can also be found in other essential proteins and another 25% is stored in your body in a blood protein called ferritin.

Detailed explanation-3: -Hemoglobin is made up of four symmetrical subunits and four heme groups. Iron associated with the heme binds oxygen. It is the iron in hemoglobin that gives blood its red color. It is easier to bind a second and third oxygen molecule to Hb than the first molecule.

Detailed explanation-4: -It is the iron atom that binds oxygen as the blood travels between the lungs and the tissues. There are four iron atoms in each molecule of hemoglobin, which accordingly can bind four molecules of oxygen.