Answer
Red blood cells (RBCs) contain hemoglobin, a pigment that attracts oxygen. The "globin" part of hemoglobin is a protein made up of four polypeptide chains, and the "heme" part of hemoglobin contains iron in the center of those polypeptide chains. This structure is the reason that hemoglobin draws in oxygen in the lungs and later releases that oxygen into tissues. Every molecule of hemoglobin can transport four oxygen molecules, and every RBC contains about 280 million hemoglobin molecules.
Work Step by Step
Red blood cells (RBCs) contain hemoglobin, a pigment that attracts oxygen. The "globin" part of hemoglobin is a protein made up of four polypeptide chains, and the "heme" part of hemoglobin contains iron in the center of those polypeptide chains. This structure is the reason that hemoglobin draws in oxygen in the lungs and later releases that oxygen into tissues. Every molecule of hemoglobin can transport four oxygen molecules, and every RBC contains about 280 million hemoglobin molecules.
