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www.GOALias.blogspot.comDid you try to observe how these seedswere clinging to your clothes?What do you think will happen if allseeds of a plant were to fall at the sameplace and grow there? There would besevere competition for sunlight, water,minerals and space. As a result the seedswould not grow into healthy plants.Plants benefit by seed dispersal. Itprevents competition between the plantand its own seedlings for sunlight, waterand minerals. It also enables the plantsto invade new habitats for widerdistribution.Seeds and fruits of plants are carriedaway by wind, water and animals.Winged seeds such as those ofdrumstick and maple [Fig. 12.13 (a) and(b)], light seeds of grasses or hairy seedsof aak (Madar) and hairy fruit ofsunflower [Fig. 12.14 (a), (b)], get blownoff with the wind to far away places.Some seeds are dispersed by water. Thesefruits or seeds usually develop floatingability in the form of spongy or fibrousouter coat as in coconut. Some seedsare dispersed by animals, especiallyspiny seeds with hooks which getattached to the bodies of animals andare carried to distant places. Examplesare Xanthium (Fig. 12.15) and Urena.Some seeds are dispersed when thefruits burst with sudden jerks. The seedsare scattered far from the parent plant.This happens in the case of castor andbalsam.SeedWing(a) (b) (a) (b)Fig. 12.13 Seeds of (a) drumstick andFig. 12.14 (a) The hairy fruit of sunflower and(b) maple(b) hairy seed of madar (aak)Fig. 12.15 Xanthium139REPRODUCTIONIN PLANTS139