ABSTRACT
Metals are an essential part of the coordination complexes. It is the presence of the metals which provide the surface area for the ligands to coordinate with them. In plants the role of boron, aluminum and barium is also important. The most important function of the metals is their ability to form complexes. Magnesium and calcium are required for structure formation and to start reaction maintains the correct rhythm of heart beat and conversion of fibrinogen to fibrin. Manganese activates all those enzymes which magnesium does—e.g. kinases synthases and dehydrogenases. The iron in all hemoproteins is either five or six coordinate etc. Iron porphyrin, proteins and enzymes are collectively known as heme proteins or hemoproteins.these proteins exhibit distinctly different functions. Oxygen transport is very important for respiration. Its production in photosynthesis provides examples of biologically important redox reaction which includes electron transfer, transfer of atom and photosyntheses processes.
