Question

The oxygen evolved during photosynthesis comes from water molecules. Which one of the following pairs of elements is involved in this reaction?

• A. Magnesium and Chlorine
• B. Manganese and Chlorine
• C. Manganese and Potassium
• D. Magnesium and Molybdenum

Answer 1

The correct option is B

Manganese and Chlorine

The oxygen evolved during photosynthesis comes from splitting of the water molecules. ​​​​​​
​This phenomenon of breaking up of water into hydrogen and oxygen in the illuminated chloroplasts is called as photolysis or photocatalytic splitting of water.
Enzymes utilize the energy obtained from absorbing light to remove electrons from water and as a byproduct release oxygen. The Manganese and Chlorine ions play a crucial role in this process.