Question

The essential element required for water splitting in photosynthesis leading to release of oxygen is

• A. Mo
• B. Mn
• C. Mg
• D. K

Answer 1

The correct option is B Mn

During ATP synthesis in the chloroplast, the proton gradient is formed. There are several processes that take place during activation of electrons and their transport which lead to the development of a proton gradient. Photolysis of water is the first process of this activation. The splitting of the water molecule takes place on the inner side of the thylakoid membrane and so the hydrogen ions (protons) that are produced, they accumulate within the lumen of the thylakoids. Oxygen-evolving complex called Z-enzyme is attached to the inner surface of the thylakoid membrane. The enzyme has four Mn ions. Light energized Mn and removes electrons from $O{H}^{-}$ component of water forming oxygen. So, the essential element required for water splitting in photosynthesis leading to release of oxygen is Mn.