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www.GOALias.blogspot.comBoojho wants to know whyflowers are generally so colourfuland fragrant. Is it to attractinsects?water. Insects visit flowers and carryaway pollen on their bodies. Some ofthe pollen lands on the stigma of a flowerof the same kind. The transfer of pollenfrom the anther to the stigma of a floweris called pollination. If the pollen landson the stigma of the same flower it iscalled self-pollination. When the pollenof a flower lands on the stigma of anotherflower of the same plant, or that of adifferent plant of the same kind, it iscalled cross-pollination [Fig. 12.10 (a)and (b)].Pollen grain (germinating)FertilisationThe cell which results after fusion ofthe gametes is called a zygote. Theprocess of fusion of male and female138(a)Pollen tubeOvum(b)ZygoteformationFig. 12.11 Fertilisation (Zygote formation)(a)(b)Fig. 12.12 (a) Section of an apple, (b) Almondgametes (to form a zygote) is calledfertilisation (Fig. 12.11). The zygotedevelops into an embryo.12.3 FRUITSAND SEEDFORMATIONAfter fertilisation, the ovary grows intoa fruit and other parts of the flower falloff. The fruit is the ripened ovary. Theseeds develop from the ovules. The seedcontains an embryo enclosed in aprotective seed coat.Some fruits are fleshy and juicy suchas mango, apple and orange. Some fruitsare hard like almonds and walnuts[Fig. 12.12 (a) and (b)].12.4 SEEDDISPERSALIn nature same kind of plants grow atdifferent places. This happens becauseseeds are dispersed to different places.Sometimes after a walk through a forestor a field or a park, you may have foundseeds or fruits sticking to your clothes.SCIENCE