Fertilization occurs in flowering plants through the process of fertilization. The center of the flower has long thin filaments with anthers at the top. This is called the stamen. Four pollen sacks are located in the plants anthers which contain MMCs, Micro Mother Cells. Each of the pollen sacks produces eight pollen grains, the sperm cells from the MMC. Once the pollen grains inside each of the sacks are ready the anthers will burst open vomiting the sticky pollen onto the flowers stamen in a process called dehiscence. The flowers bright colorful pedals lure insects inside to drink its nectar, located at the flowers base. Once the insects climb into the flower the sticky pollen from the anthers gets stuck on its feet, legs, or body. In the process of cross pollination the insect that collects this sticky pollen will transfer it to another flower pollinating it in the process. In the process of self pollination the pollen will be moved from the stamen to the pistol/carpal of the flower, which is located in the flowers center surrounded by the stamen. The carpal of the flower holds the females organs which is made up of the stigma and the ovary. The ovules/eggs are in the base of this tube inside the ovary. Once a spore lands on the stigma, it sends a tube down to the ovum. When the tip reaches the ovule it releases two male gametes. One gamete fuses with the ovule while the other fuses with the polar nuclei, this process is called double fertilization. Then the will start to become a seed, and ovary develops a fleshy outside which will be the fruit.
Brassica oleracea:
Anther:
Anthers hold the pollen that contain the sperm necessary for reproduction. The long filaments hold the anthers up from the center of the flower to increase the flowers chances of a pollinator climbing inside the flower and collecting the sticky pollen off the anthers, which allow the process of cross and self pollination to occur. Without the anthers producing the sperm and the pollen, the flower can't reproduce.
Stigma:
The stigma of the flower receives the pollen grains during the process of pollination. The surface of the stigma acts as a sticky catching device of the pollen grains ,used in fertilization, because of the exudate produced by the epidermal cells. The stigma provides water and nutrients that the pollen grains need during germination.
Ovule(s):
The ovules are a big part of the process of fertilization in a flower by collecting and fusing with the two male gametes released from the tip of a tube in the stigma which travels into the ovum once having collected pollen. The ovule also helps protect the nucellus containing the females gametophyte and the endo sperm along with the developing embryo.
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