Red Blood Cells
I am erythrocytes, or otherwise known as red blood cells. I have one of the most important roles in the entire body. Out of all kinds of blood cells, I am the most numerous. My job in the body is to carry oxygen and carbon dioxide throughout the body. I contain lots of iron, which is how I transport the oxygen and carbon dioxide around. While I am floating around the blood, the iron magnetically attracts the molecules, the molecules attach to me, and then I transport them all around the body. On average, men have about 5,400,000 per cubic millimeter. Women, on the other hand, average only 4,800,000 per cubic millimeter. A single drop of blood can contain over one million of me. On average, I am about 7.5 thousands of a millimeter wide. Because my only purpose is to transport oxygen and carbon dioxide, when I am made, the nucleus is squeezed out of my cell.
Macrophages that are near eat the nucleus, then break down the DNA.
The only reason that I am red is because I contain a special protein chemical called hemoglobin. Hemoglobin contains iron, which is what is used to make the oxygen and molecule attach to me. If the hemoglobin were not in the cells, all of your blood would be yellow-colored. Once I pass through the body tissue, the hemoglobin releases all of the oxygen and molecules out to all of the cells. The hemoglobin that is left over then bonds with carbon dioxide, or whatever other waste gasses there are in the body, then transports it all away (Riding on the Red Road 1).
One thing that is unique about me is that I am terminally differentiated. This means that I can never divide. I live for approximately...