Q.Students were on the excursion to a botanical garden. They noted following observation. Will you be able to help them in understanding those conditions? A plant was found growing on other plant. Teacher said it is not a parasite. It exhibited two types of roots.

Roots develop structural changes (metamorphosis) to take on extra functions. Tap root modifications: food storage produces swollen roots of three shapes — fusiform, broad in the middle and tapering at both ends (Radish); conical, broad at the base narrowing to the tip (Carrot); and napiform, a near-spherical swollen base narrowing abruptly (Beet) — while some mangrove tap roots bear lenticels for gaseous exchange. Adventitious root modifications are more varied: food storage gives simple tuberous (single swollen root, e.g. sweet potato), fasciculated tuberous (a fleshy cluster at the stem base, e.g. Dahlia), beaded/moniliform (bead-like swellings, e.g. Spinacia) and nodulose (tip-swollen clusters, e.g. Maranta) roots; respiration is served by negatively geotropic pneumatophores that rise above waterlogged mangrove soil; mechanical support is provided by prop/columnar roots (Banyan), stilt roots (Maize and other Poaceae), climbing roots (betel leaf, black pepper, money plant), clinging …