Q.Write on macronutrients and micronutrients required for plant growth.

Step 1. Macronutrients. Macroelements are required by the plant in large quantity and mainly play nutritive and structural roles; they include C, H, O, P, Mg, N, K, S, Ca and Fe (with C, H and O being non-mineral in origin). Examples of their roles: nitrogen builds proteins, nucleic acids and chlorophyll; phosphorus builds membranes and nucleotides and drives phosphorylation; potassium maintains ion balance and turgidity; calcium maintains membrane permeability and the middle lamella; magnesium is a chlorophyll constituent; sulphur builds certain proteins and vitamins.

Step 2. Micronutrients. Microelements (trace elements) are required only in minute amounts because they function mainly as catalytic cofactors for enzymes; they include Zn, Cu, Al, Si, Mn, B, Mo and Cl. Examples of their roles: iron and manganese activate enzymes involved in chlorophyll synthesis and general catalysis; molybdenum activates nitrogen-metabolism enzymes; boron is needed for calcium uptake and pollen germination; zinc activates carboxylases and enzymes needed for auxin synthesis; chlorine assists ion balance and photosynthetic oxygen evolution. …

Define both categories, list their member elements, and give representative roles …

• Omitting that C, H and O, though major/macro elements, are not of mineral origin
• Listing an element's deficiency symptom without also stating its functional role, when the que …