The iron-containing pigment which forms the oxygen-binding site of haemoglobin and myoglobin. It is also part of a variety of other proteins, collectively known as haem proteins, including the cytochromes.
A molecule containing iron which binds proteins to form haemoproteins such as haemoglobin and myoglobin.
An iron-containing porphyrin compound that combines with the protein globulin to make haemoglobin, a constituent of erythrocytes (red blood cells).
Heme is an iron-containing pigment that combines with globin, a protein, to create hemoglobin—the primary component of red blood cells. Hemoglobin binds with oxygen to facilitate its transportation from the lungs to the body tissues.