This element is found in rubredoxin proteins, where it is coordinated by four cysteine residues. (-5[1])Proteins that catalyze redox reactions often have clusters of this element and sulfur. (10[1])An ion of this element is found in the active site of an enzyme that degrades hydrogen peroxide, catalase. A protein that contains an ion of this element transitions from a T to R state upon oxygen binding. (10[3])That protein (10[1])is also compromised in individuals with thalassemia, (10[1])and the heme group is responsible for (10[1])binding (10[1])an ion of this element. (10[2])A deficiency of this element in the body results in anemia. (10[1])For 10 points, name this metallic element whose ion gives blood its red color. ■END■ (10[1])