Iron

**Definition:** A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.

**Tree numbers:** - D01.268.556.412 - D01.268.956.287 - D01.552.544.412

**Synonyms:** - Iron-56