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# Reproduction in Angiosperms ## 5.2 Sexual Reproduction of Angiosperms ### 5.2.1 Definition Sexual reproduction is the creation of a new individual through fertilization, which is the fusion of two cells. In angiosperms, this process occurs within the reproductive organs, the flowers. ### 5.2....

# Reproduction in Angiosperms ## 5.2 Sexual Reproduction of Angiosperms ### 5.2.1 Definition Sexual reproduction is the creation of a new individual through fertilization, which is the fusion of two cells. In angiosperms, this process occurs within the reproductive organs, the flowers. ### 5.2.2 Meiosis To form male and female reproductive cells (gametes), certain cells in the stamens and ovules undergo meiosis. Meiosis is a series of two divisions (reductional and equational divisions) where the number of chromosomes is halved. This reduction in chromosome number is critical to prevent the chromosome count from doubling with each fertilization. For example, a lily has 22 chromosomes in its normal cells (diploid cells, 2n=22). After meiosis, the reproductive cells have only 11 chromosomes (haploid cells, n=11). When the male gamete (pollen grain) fuses with the female gamete (in the ovule’s embryo sac), the resulting embryo will have 22 chromosomes once again. ## Formation of Pollen Grains Stamens typically consist of a filament and an anther. Meiosis inside the anther creates four haploid cells with half the number of chromosomes. These haploid cells undergo a final maturation division, creating the pollen grains. Each pollen grain contains a generative nucleus and a vegetative nucleus. Different plant species have distinct pollen grain appearances. ### Diagrams The provided document includes diagrams depicting the process of meiosis. The diagrams show the stages of cell division, from a single cell to multiple cells, with annotations showing the changing number of chromosomes. Unfortunately, a more precise technical description of these diagrams isn't possible without greater detail in the image.