Choose the correct statements about different types of cycles in plants – A. Nitrogen cycle describes transition of nitrogen from atmospheric nitrogen to organic nitrogen B. Water cycle is a constant cycle through which Earth’s water moves in solid, liquid or gaseous stages C. Carbon cycle is the movement of carbon through different reservoirs of Earth’s ecosystem D. Calvin cycle is a part of photosynthesis in which carbon dioxide is turned into simple sugars

Correct option is C

The correct answer is (C) A, B, C, D

Explanation:
• All statements are correct.
• Statement A: The nitrogen cycle involves nitrogen fixation, nitrification, and denitrification to convert N2 into usable organic forms.
• Statement B: The water cycle (hydrologic cycle) involves evaporation, transpiration, condensation, and precipitation.
• Statement C: The carbon cycle regulates the Earth's climate by moving carbon between the atmosphere, oceans, and living organisms.
• Statement D: The Calvin cycle (C3 cycle) takes place in the stroma of chloroplasts during the light-independent reactions of photosynthesis.

Information Booster:
• The Nitrogen cycle is vital because atmospheric nitrogen (78%) cannot be used directly by most organisms; it must be "fixed" by bacteria or lightning.
• The Calvin cycle uses ATP and NADPH produced in light-dependent reactions to fix CO2 into glucose.

Additional Knowledge:
• Carbon is stored in "sinks" like forests and oceans.
• The disruption of these cycles (like excessive carbon emission) leads to global environmental issues such as global warming.