Development of Female Gamete and Embryo Sac in Plant Reproduction
In plant reproduction, the formation of female gametes involves meiosis in cells of the carpel sac, leading to the development of the embryo sac or megaspore. Meiosis results in four haploid cells, of which three degenerate, and one survives. This surviving cell undergoes multiple rounds of mitosis, leading to the generation of an embryo sac with eight nuclei. Within the embryo sac, two polar nuclei and the egg cell survive, while other nuclei perish. Double fertilization occurs when a male gamete from a pollen grain fuses with the egg nucleus to form an embryo plant, while the polar nuclei combine with the second cell to create endosperm. This process ultimately results in the formation of a seed, with the integument forming the protective testa layer around it.
Download Presentation
Please find below an Image/Link to download the presentation.
The content on the website is provided AS IS for your information and personal use only. It may not be sold, licensed, or shared on other websites without obtaining consent from the author. Download presentation by click this link. If you encounter any issues during the download, it is possible that the publisher has removed the file from their server.
E N D
Presentation Transcript
Formation of Female Gamete Embryo Sac Development
Cells of Carpel Sac are 2n Cell in Ovule divide by Meiosis and it becomes the embryo sac or Megaspore
Meiosis 4 Haploid Cells are made 3 die and 1 survive
Cell Division Mitosis Mitosis Mitosis
8 Nuclei The Embryo Sac swells and now contains 8 nuclei This is also called the Megaspore
Nuclei in Embryo Sac 2 Polar Nuclei Polar Nuclei and Egg Cell survive Egg Cell Other Nuclei die
Double Fertilisation 1 male gamete from the pollen grain fuses with the egg nucleus to form the embryo plant Polar Nuclei join with the 2nd Cell form pollen grain to form Endosperm No water needed Adaptation to life on land Fertilised Ovule = Seed Integument = Testa
