Oxygen is primarily transported in the blood through the binding with hemoglobin, a protein found in red blood cells. Hemoglobin forms a reversible complex with oxygen, creating oxyhemoglobin. In the lungs, where oxygen concentration is high, hemoglobin binds with oxygen, and in oxygen-deficient tissues, it releases oxygen. This mechanism ensures efficient and adaptable oxygen transport, responding to the varying oxygen demands of different body parts. The high affinity of hemoglobin for oxygen allows for the effective loading and unloading of oxygen, contributing to the respiratory process and sustaining aerobic metabolism in cells throughout the body.