Sexual reproduction in plant involves the fusion of the male and female gamete to form an embryo or seed. Flower is reproductive organ of the plant, in some plants' flowers, the male and female reproductive organs are together in the same flower while in some they are in separate plants. A flower which has both male and female organs in the plant is called a complete flower while the flower which has it female and male in different flower or plant is called incomplete flower.
The male reproductive organ or parts include the stamen, which is make up of the anther (which produces the pollen) and the filament(which holds the anther)
The female organs include the pistil, which consist of the stigma(which receives the pollen), the style, a tube connecting the stigma to the ovary, and the ovary contains the ovule.
Pollination and Fertilization
the transfer of the pollen from the anther of male flower to the stigma of the female flower is called pollination. Pollination is very important process because without it the zygote or seed will not be formed. Depending on the method of landing of pollen to the stigma, pollination can be classified into two which are:
* self- pollination
* cross-pollination
Self- pollination: this type of pollination occurs when pollen is transferred between the anther and stigma of the same plant.
Cross-pollination : occurs when the pollen is transferred between different plants. it encourages genetic diversity.
Fertilization
The pollen grains germinate , after pollination, and develop a tube known as pollen tube which moves down the style to the ovary. the tube leads the male gametes to the ovule within the ovary where fertilization occurs. Fertilization is the fusion of male and female gametes inside the ovule. this fusion forms the zygote or embryo.
Seed and Fruit Development
The fertilized ovule develops into a seed, which contains the embryo (the new plant) and a food supply (endosperm).
The ovary surrounding the ovule develops into a fruit, which protects the seed and aids in its dispersal.
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