Welcome Biology Students!
Dive into our expertly crafted content covering all aspects of biology, from basic cell structure to complex genetics, tailored specifically for NEET aspirants and students across grades 6-12.
💎 3 GOLDEN FACTS (NEET 2019-24)
⚖️ ULTIMATE PHOTOSYNTHESIS COMPARISON
| Parameter | C3 | C4 | CAM |
|---|---|---|---|
| First Product | PGA (3C) | OAA (4C) | Malate (4C) |
| Rubisco Activity | High | Only in BS cells | Night only |
| NEET Frequency | 3 Q/yr | 2 Q/yr | 1 Q/2yr |
🚨 NEET ALERT!
Photorespiration asked 3 years consecutively - Master it now!
☀️ Light Reaction (Photochemical Phase)
Location: Thylakoid membranes of chloroplasts
Photosystems:
- PS-II (P680): Water splitting (Photolysis), releases O₂, protons, and electrons
- PS-I (P700): NADP⁺ reduction to NADPH via Ferredoxin
Photophosphorylation:
- Non-cyclic: Produces ATP + NADPH + O₂ (Z-scheme)
- Cyclic: Only ATP is produced (involves only PS-I)
Chemiosmotic Hypothesis: Proton gradient drives ATP synthesis via ATP synthase
🎯 PYQ Highlights:
NEET 2021: Which pigment acts as the reaction center in PS-I? Answer: P700
NEET 2019: During cyclic photophosphorylation, which molecule is not produced? Answer: NADPH
🧬 Z-Scheme Decoded
PSII → Pheo → PQ → Cyt → PC → PSI → Fd → NADP+
680nm → 700nm | H₂O split at PSII
NEET Hack: "PhotoPETE (PSII) → CYTOchrome → PhotoPETE (PSI)"
📈 Recent Trends & Expected Questions
NEET 2023: Focused on comparison between C3, C4, CAM plants
NEET 2022: Asked about ATP yield in cyclic vs non-cyclic phosphorylation
NEET 2021: Diagram-based question on Z-scheme of light reaction
Probable Questions for 2024:
- Role of Mg²⁺ in chlorophyll structure
- Why does RuBisCO have a higher affinity for CO₂ than O₂?
- Difference between Hatch-Slack & Calvin cycle
🧠Mnemonics & Quick Recall
PS-II → ATP
PS-I → NADPH
CO₂ → OAA → Oxaloacetate → Less photorespiration
💡 Final Tips for NEET
- ✅ Memorize ATP/NADPH counts (Light & Dark reactions)
- ✅ Practice diagram labelling (Chloroplast structure, Z-scheme)
- ✅ Revise exceptions (CAM plants open stomata at night)
With these insights, you're set to tackle any photosynthesis question in NEET! Best of luck! 🚀
🚨 NEET ALERT!
Photorespiration asked 3 years consecutively - Master it now!
