What role do red blood cells play in the human body?

Red blood cells carry oxygen around the body. These specialized cells are outfitted with the substance hemoglobin, which is a protein, and is the actual oxygen carrying molecule on the cell. The cell has a unique shape that allows it to carry as much oxygen molecules as possible. Red blood cells also transport carbon dioxide away from cells and back to the lungs where the cells are then re-oxygenated.

Remove carbon dioxide from your body, transporting it to the lungs for you to exhale