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  • Our topic for today is Sexual reproduction in flowering plants.

  • Let us learn about the male and female reproductive parts of flowering plants.

  • Stamen is the male reproductive part of the flower.

  • It consists of the anther and the filament.

  • The anther produces pollen grains.

  • Each matured pollen grain contains a tube cell consisting of a tube nucleus and two male gametes.

  • Carpel is the female reproductive part of the flower.

  • Top part of the carpel is called the stigma.

  • Stigma is supported by the style.

  • Base part of the carpel is the ovary.

  • Ovary contains one or more ovules.

  • Each ovule has a female gamete.

  • Flowers that contain both male and female reproductive parts are called bisexual flowers.

  • Hibiscus and rose are some examples of bisexual flowers.

  • Flowers that contain either male or female reproductive parts are called unisexual flowers.

  • Papaya and watermelon are some examples of unisexual flowers.

  • For fertilization to take place, pollen grains need to be transferred from the stamen to the stigma.

  • If the transfer of pollen grain takes place in the same flower, then it is called self pollination.

  • If the transfer of pollen grain takes place from one flower to another, then it is called cross pollination.

  • This transfer of pollen grains is done by wind, water, insects or animals.

  • After the pollen grain lands on the stigma, the tube cell produces a pollen tube through the style into the ovule.

  • The male gametes travel along with the tube nucleus through the pollen tube.

  • After they reach the ovule, one of the male gametes fuses with the female gamete leading to fertilization.

  • Fertilization leads to the formation of zygote.

  • The other male gamete fuses with the polar nuclei to eventually form endosperm.

  • The zygote divides multiple times to form an embryo within the ovule.

  • The endosperm provides nourishment to the embryo.

  • Eventually, the ovule develops and turns into a seed.

Our topic for today is Sexual reproduction in flowering plants.

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B2 中高級 美國腔

開花植物的有性繁殖|#aumsum (Sexual Reproduction in Flowering Plants | #aumsum)

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    AumSum 發佈於 2021 年 01 月 14 日
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