NEET2011BotanyPhotosynthesis in Higher PlantsActual
Assertion : Protons or hydrogen ions produced by photolysis of water accumulate in the lumen of thylakoids. Reason : Photolysis of water takes place in inner membrane of thylakoid.
Options
- AIf both assertion and reason are true and reason is the correct explanation of assertion
- BIf both assertion and reason are true but reason is not the correct explanation of assertion
- CIf assertion is true but reason is false
- DIf both assertion and reason are false.
Correct answer
B. If both assertion and reason are true but reason is not the correct explanation of assertion
Step-by-step solution
The first step in photosynthesis is the light-driven oxidation (splitting or photolysis) of water. It provides the electrons for the photosynthetic electron transport chains as well as protons for the establishment of a proton gradient. It occurs on the lumenal side of the thylakoid membrane. During photolysis, water is oxidised to oxygen, protons and electrons. Protons accumulate in the lumen.