MSH: 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.,CSP: metallic element found in certain minerals, in nearly all soils, and in mineral waters; atomic symbol Fe, atomic number 26, and atomic weight 55.85; it is an essential constituent of hemoglobin, cytochrome, and other components of respiratory enzyme systems; chief function is in the transport of oxygen to tissue (hemoglobin) and in cellular oxidation mechanisms.,MEDLINEPLUS: Iron is a mineral that our bodies need for many functions. The body needs iron to make the proteins hemoglobin and myoglobin. Hemoglobin is found in red blood cells and myoglobin is found in muscles. They help carry and store oxygen in the body. Iron is also part of many other proteins and enzymes in the body. Your body needs the right amount of iron. If you have too little ir