Key Points — 5-Bullet Ultra-Brief — Summary

Light reactions (thylakoid membranes): PS II (P680) splits water → $O_{2}$ ; Z-scheme → NADPH; Chemiosmosis ( $CF_{0}$ - $CF_{1}$ ) → ATP; Non-cyclic (PS I+II) = ATP+NADPH+ $O_{2}$ ; Cyclic (PS I only) = ATP only (stroma lamellae).
Calvin cycle (stroma): C $O_{2}$ + RuBP → 3-PGA (RuBisCO) → G3P (18 ATP + 12 NADPH/glucose) → RuBP regenerated. First product = 3-PGA. 18 ATP + 12 NADPH (not 12+12).
C4 plants (maize, sugarcane): Kranz anatomy, PEP carboxylase (mesophyll) → OAA (4C, first product), no photorespiration, 30–40°C optimal.
CAM plants (cacti, Bryophyllum): C $O_{2}$ fixed at night (PEP → malic acid in vacuole), Calvin cycle in day (stomata closed), highest WUE.
Top NEET traps: PS II acts first (not PS I); cyclic = ATP only; 18 ATP per glucose (not 12); $O_{2}$ from water (Van Niel); C4 first product = OAA (not 3-PGA).