Graphic by John Ryan
Red blood cells are also called erythrocytes. A red blood cell looks like a double dented balloon. They use the blood vessels to get around in the entire body giving oxygen they got as a gift from the lung cells and they pass it around to all the other cells
Red blood cells have hemoglobin in them. Hemoglobin is the stuff that makes the oxygen get in and makes the erythrocyte a red color. Red blood cells take the carbon dioxide out of the body. Carbon dioxide is like used air, so the red blood cells work kind of like a car's exhaust pipe. An exhaust pipe gets rid of used air in the car, and red blood cells get rid of used air in the blood.Compare: If you have an air conditioner or heater in your house, then you have something that works like red blood cells: a filter. How is a filter's job like a red blood cell's job?
