NBC 105 • Unit 210 min read★ High Exam Frequency
Carbon & Nitrogen Cycles, Water Resources & Renewable Energy
Unit 2: Natural Resources & Biogeochemical Cycles • Environment and Ecology
👨🏫 Professor's Mental Model: Nature's Infinite Recycling Loop
Earth par naya paani ya carbon kahin bahar se nahi aata. Jo paani dinosaurs ne piya tha, wahi water cycle se ghuma kar aaj hum pee rahe hain! Biogeochemical cycles nature ke infinite circular buffers hain!
The Nitrogen Cycle Phases
1. Nitrogen Fixation: Atmospheric N2 fixed into NH3 by Rhizobium / Azotobacter.
2. Nitrification: NH3 -> NO2- (Nitrosomonas) -> NO3- (Nitrobacter).
3. Assimilation: Plants absorb nitrates for proteins.
4. Ammonification & Denitrification: Pseudomonas converts nitrates back into atmospheric N2 gas.
Energy Resources: Conventional vs Renewable
Conventional: Coal, Petroleum, Natural Gas, Nuclear (finite, carbon emitting).
Renewable: Solar Photovoltaics, Wind Turbines, Hydroelectric, Biomass, Geothermal, Tidal energy.
🎯 University Exam Scoring Blueprint
- Draw the complete Nitrogen cycle with bacteria names.
- Explain Fluorosis (excess fluoride) and Arsenicosis (arsenic in drinking water).
Top Viva Questions on Carbon & Nitrogen Cycles, Water Resources & Renewable Energy
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