FERTILIZATION IS THE FUSION of male and female gametes (sex cells) to produce Zygote (embryo).
Following pollination , the pollen grains that contain the male gametes are on the stigma , some distance from the female gamete
(ovum) inside the ovule .To enable the gametes to meet, the pollen grain germinates and produces a pollen tube , which grows down and enters the embryo sack ( the inner part of the ovule that contains the ovum).Two male gametes , travelling at the tip of the pollen tube ,enter the embryo sac .ne gamete Ose with the ovum to produce a zygote that will develop into embryo plant .The other male gametes fuses with two polar nuclei to produce the endosperm , which act as a food store for the developing embryo.
Fertilization also initiate other changes ;the integument (outer part of ovule ) forms a testa (seed coat) around the embryo and endosperm , the petals falls off;the stigma and style wither and the ovary wall forms a layer (called the paricarp)around the seed .Together the paricarp and seed form the fruit , which may be succulent or dry.In some species (e.gatblackberry) ,apomixis can occur ;the seed develop without fertilization of the ovum by a male gamete but
enodosperm formation and fruit development takes place as in other species.
Following pollination , the pollen grains that contain the male gametes are on the stigma , some distance from the female gamete
(ovum) inside the ovule .To enable the gametes to meet, the pollen grain germinates and produces a pollen tube , which grows down and enters the embryo sack ( the inner part of the ovule that contains the ovum).Two male gametes , travelling at the tip of the pollen tube ,enter the embryo sac .ne gamete Ose with the ovum to produce a zygote that will develop into embryo plant .The other male gametes fuses with two polar nuclei to produce the endosperm , which act as a food store for the developing embryo.
Fertilization also initiate other changes ;the integument (outer part of ovule ) forms a testa (seed coat) around the embryo and endosperm , the petals falls off;the stigma and style wither and the ovary wall forms a layer (called the paricarp)around the seed .Together the paricarp and seed form the fruit , which may be succulent or dry.In some species (e.gatblackberry) ,apomixis can occur ;the seed develop without fertilization of the ovum by a male gamete but
enodosperm formation and fruit development takes place as in other species.
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