are erythrocytes filled with hemoglobin
Red blood cells are also known as erythrocytes. The red blood cells transport oxygen through the circulatory system to the cells and tissues of the body. In the cells, oxygen and glucose support glycolysis, the production of ATP (adenosine triphosphate). The red blood cells are filled with hemoglobin, the oxygen-carrying part of the red blood cell. Hemoglobin can also be spelled âhaemoglobin.â Each red blood cell contains 250 to 300 million molecules of hemoglobin. A molecule of hemoglobin is made up of one globin protein, with four iron-containing heme groups.