The component of blood that transports both carbon dioxide and urea in the body is the plasma. Plasma is the liquid part of blood that carries carbon dioxide (mostly dissolved or in the form of bicarbonate ions) and urea, as well as other substances like digested food, hormones, and heat energy. While red blood cells primarily transport oxygen and also carry some carbon dioxide bound to hemoglobin, the main transporter of carbon dioxide in the blood in dissolved and converted forms, along with urea, is plasma.