Which component of the blood is primarily responsible for the transportation of oxygen?

Erythrocytes, also known as red blood cells, are primarily responsible for the transportation of oxygen in the blood. They contain a protein called hemoglobin, which binds to oxygen in the lungs and carries it to tissues throughout the body. Each hemoglobin molecule can bind up to four oxygen molecules, making erythrocytes highly efficient at delivering oxygen where it is needed.

In contrast, platelets are involved in the clotting process, helping to stop bleeding. Leukocytes, or white blood cells, play a crucial role in the immune system by defending the body against infections. Plasma, the liquid component of blood, primarily serves as a medium for transporting nutrients, hormones, and waste products rather than gases like oxygen. Thus, the unique structure and function of erythrocytes make them the key players in oxygen transport within the circulatory system.