Mature red blood cells are filled with hemoglobin. Hemoglobin attracts gaseous elements. Through the path of circulation, red blood cells transport carbon dioxide out of the body in the region of the lungs and acquire new oxygen which is attracted to the hemoglobin and circulates through the body to deliver fresh oxygen to the cells of the body, completing the cycle. Red blood cells are created in your bone marrow and exist for about 6 months in the body.
