describe the process of fertilisation in a flower.
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The male component of fertilization in flowering plants is pollen. It consists of two or three gametophytes containing the tube cell and germ cell. The tube cell grows into a pollen tube, while the germ cell divides through mitosis. Pollination brings the male pollen into the female stigma of a flower with the help of pollinators. Large flowers mostly attract insect pollinators, while smaller flowers use the wind to pollinate. The pollen is then transferred into the pistil or gynoecium, which contains the stigma, receptacle, ovary and style. Its tube cell sticks to the receptive stigma and starts to develop into a pollen tube. The male germ cell releases two sperm cells that travel to reach the flower’s ovum. While the male cell grows, the female cell in the ovule develops. One of the sperm cells fuses with the egg, while the other forms an endosperm tissue, which serves to nourish the growing zygote or seed. After fertilization occurs, the ovary wall becomes a fruit.
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e male and female flowers on different plants. Many have the stigmas and anthers ripening at different times to prevent self-pollination.
Fertilisation
Only after pollination, when pollen has landed on the stigma of a suitable flower of the same species, can a chain of events happen that ends in the making of seeds. A pollen grain on the stigma grows a tiny tube, all the way down the style to the ovary. This pollen tube carries a male gamete to meet a female gamete in an ovule. In a process called fertilisation, the two gametes join and their chromosomes combine, so that the fertilised cell contains a normal complement of chromosomes, with some from each parent flower.
The fertilised ovule goes on to form a seed, which contains a food store and an embryo that will later grow into a new plant. The ovary develops into a fruit to protect the seed. Some flowers, such as avocados, only have one ovule in their ovary, so their fruit only has one seed. Many flowers, such as kiwifruit, have lots of ovules in their ovary, so their fruit contains many seeds.
Fertilisation
Only after pollination, when pollen has landed on the stigma of a suitable flower of the same species, can a chain of events happen that ends in the making of seeds. A pollen grain on the stigma grows a tiny tube, all the way down the style to the ovary. This pollen tube carries a male gamete to meet a female gamete in an ovule. In a process called fertilisation, the two gametes join and their chromosomes combine, so that the fertilised cell contains a normal complement of chromosomes, with some from each parent flower.
The fertilised ovule goes on to form a seed, which contains a food store and an embryo that will later grow into a new plant. The ovary develops into a fruit to protect the seed. Some flowers, such as avocados, only have one ovule in their ovary, so their fruit only has one seed. Many flowers, such as kiwifruit, have lots of ovules in their ovary, so their fruit contains many seeds.
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