photosynthesis — NEET/JEE Questions, Notes & Weightage
Covers light reactions, the Calvin cycle (C3), C4 and CAM pathways, photorespiration, and factors affecting photosynthetic rate. One of Biology's most exam-dense chapters — C3 vs C4 plant comparisons and the electron-transport-chain sequence are near-certain NEET topics.
Practice all 5 photosynthesis questions →Topics inside photosynthesis
Frequently asked questions
What is the single most important comparison in this chapter?
C3 vs C4 photosynthesis — anatomical (Kranz anatomy), biochemical (enzyme: RuBisCO vs PEP carboxylase), and efficiency differences are tested from multiple angles almost every year.
How detailed do I need to know the light reaction electron flow?
Quite detailed — the sequence through PS II → electron transport chain → PS I → NADPH formation, and where ATP synthesis (photophosphorylation) occurs, is regularly tested.
Is photorespiration commonly confused with respiration?
Yes, and NEET exploits that — know that photorespiration consumes O2/releases CO2 in the light, uses RuBisCO oxygenase activity, and lowers C3-plant photosynthetic efficiency, unlike normal respiration.