Which micronutrient is required for splitting of water molecule during photosynthesis?
Answer: (A) manganese. Splitting (photolysis) of water during the light reaction is carried out by the water-splitting (oxygen-evolving) complex associated with PS II, which uses manganese (along with Cl- and Ca2+) at its active centre.
- A.manganese✓
- B.molybdenum
- C.magnesium
- D.copper
Correct Answer
(A) manganese
Solution & Explanation
Splitting (photolysis) of water during the light reaction is carried out by the water-splitting (oxygen-evolving) complex associated with PS II, which uses manganese (along with Cl- and Ca2+) at its active centre. Among the options, manganese is the micronutrient required for water splitting; molybdenum, magnesium and copper have other roles. NCERT Ch11 describes the water-splitting reaction but the specific Mn requirement is established mineral-nutrition knowledge applied here. NCERT: Class 11 Ch 11, p.139 [139:028-029]: "The splitting of water is associated with the PS II; water is split into 2H+, [O] and electrons" Note: Answer A (manganese) is correct, but NCERT Ch11 (Photosynthesis) does NOT name manganese in the water-splitting section; the Mn requirement comes from the Mineral Nutrition chapter. Cited the closest Ch11 supporting line (the water-splitting reaction); the Mn-specific claim is not verbatim in pages 133-152.