Red Blood Cells
Red blood cells make up approximately 40-45 percent of your blood. Red blood cells (RBC's) are produced in the bone marrow of long bones, such as the femur and the humerus, along with flat bones like the skull. If the need for red blood cells goes up then yellow bone marrow can and will be replaced with red bone marrow so it can produce more red blood cells. Erythropoietin is a protein that triggers the production of red blood cells. The normal range of red blood cells for women is 37-47% RBC's per microliter of blood, and for males it is about 40-54%. These differences are caused because of the women's special time of month, and because of the hormone differences between
hemoglobin
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Hemoglobin is a red protein that transports oxygen. There are about 280 million hemoglobin in one red blood cell. Hemoglobin is made of four units of heme and four units of iron. Hemoglobin is what gives red blood cells their red color.
What do red blood cells do?
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Red Blood Cells are completely dedicated to what they do. They transport respiratory gas. (oxygen and carbon dioxide) You can find hemoglobin in red blood cells which is the protein that makes oxygen bind so easily to red blood cells. Oxygen loading occurs in the lungs, and gets transported to the tissue cells. Then it gets loaded with used oxygen or carbon dioxide and gets taken back to the heart where it is then taken back to the lungs and reloaded again.