This element is found in rubredoxin proteins, where it (10[1])is coordinated by four cysteine residues. (-5[1])Proteins that catalyze redox reactions often have clusters of this element and sulfur. (10[3])An ion (10[2]-5[1])of this element (10[2])is found (-5[1])in the active site of an enzyme (-5[1])that degrades hydrogen peroxide, catalase. A protein that contains an ion of this element transitions from a T (10[1])to R state (10[2])upon oxygen (10[1])binding. (10[9])That (10[1])protein (10[3])is also compromised (10[2]-5[1])in individuals with (10[2])thalassemia, (10[1])and the heme group (10[1])is responsible for (10[1])binding (10[1])an ion (10[2])of this element. (10[4]-5[1])A deficiency (10[3])of this element in the body (10[2])results in anemia. (10[4])For 10 points, name this (10[1])metallic element (10[1])whose ion gives blood its red color. (10[2])■END■ (10[2])