Oxygen transport refers to the process by which oxygen is carried from the lungs to the body's tissues. In humans, this occurs primarily through the bloodstream, where hemoglobin, a protein in red blood cells, binds to oxygen molecules. When we breathe in, oxygen enters the lungs and diffuses into the blood, where it attaches to hemoglobin for distribution. Once in the bloodstream, the oxygen-rich blood travels through the arteries to various organs and tissues. At the cellular level, oxygen is released from hemoglobin and utilized for energy production during cellular respiration, which is essential for maintaining life and supporting bodily functions.