Which of the following is primarily responsible for oxygen transport in the blood?

Red blood cells are primarily responsible for the transport of oxygen in the blood due to the presence of hemoglobin, a specialized protein that binds oxygen molecules. Hemoglobin allows red blood cells to pick up oxygen in the lungs and deliver it to tissues throughout the body. This efficient mechanism of oxygen transport is vital for cellular respiration and the overall function of organs and tissues.

While white blood cells play a crucial role in the immune response and platelets are essential for blood clotting, they do not have a primary function in oxygen transport. Plasma, the liquid component of blood, primarily carries nutrients, hormones, and waste products but does not significantly contribute to the transport of oxygen. Thus, red blood cells are uniquely designed to fulfill the essential role of oxygen delivery in the circulatory system.