Oxygen Transport: The Roles of Hemoglobin and Myoglobin

Vertebrate animals use hemoglobin and myoglobin to provide their tissues with a continuous O2 supply.

Hemoglobin transports O2 from the lungs or gills to the respiring tissues, where it is used for aerobic metabolism in the mitochondria.

Inside cells, dissolved O2 diffuses freely or is bound to myoglobin, which aids transport of O2 to the mitochondria.

Myoglobin can also store O2 for later use (as in deep-diving mammals).

CO2 produced by oxidative processes in the tissues is carried back to the lungs or gills by hemoglobin and released.