What is the role of the enzyme RuBisCO in photosynthesis?
- AIt fixes carbon dioxide to produce carbohydrate.
- BIt regulates stomatal opening and closing for gaseous exchange.
- CIt catalyses the splitting of water molecules to generate oxygen.
- DIt is involved in the electron transport chain to generate ATP.
Show answer and explanation
Correct answer: (a) It fixes carbon dioxide to produce carbohydrate.
Explanation
RuBisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) is the enzyme that fixes carbon dioxide in the Calvin cycle. It joins CO₂ to ribulose-1,5-bisphosphate to form two molecules of 3-phosphoglycerate, which are then turned into sugars.
- Stomata are opened and closed by guard cells, not by RuBisCO.
- Water is split by the oxygen-evolving complex of photosystem II.
- ATP is made by the electron transport chain and ATP synthase.