The component of blood responsible for transporting oxygen is hemoglobin, a protein found within red blood cells (erythrocytes). Hemoglobin binds oxygen in the lungs and carries it through the bloodstream to tissues and organs. Each hemoglobin molecule can bind to four oxygen molecules, enhancing the efficiency of oxygen transport. The release of oxygen occurs in tissues where it is needed for cellular respiration. Additionally, hemoglobin also plays a role in transporting carbon dioxide back to the lungs for exhalation. This cyclical process is critical for maintaining homeostasis in the body.