Pollen grain with pollen tube x400. This grain has been germinated in sugar water. When a pollen grain germinates, one of its two nuclei divides by mitosis to produce two sperm nuclei. The generative nucleus and then the two sperm nuclei follow the tip of the pollen tube as it grows toward the ovary and the ovules inside. A germinated pollen grain with pollen tube and three haploid nuclei is the mature male gametophyte in flowering plants.
Pollen tubes grow down the hollow center of the style as they head toward the ovary.
Female Gametophyte development, Meiosis, Fertilization Within this group study the illustrations in the sequence. Thus, in an ovary cross section like the one illustrated you can see six ovules in various stages of development. The flaps of tissue on either side of the megaspore mother cell are seed coats. Metaphase I x400. Meiosis of the megaspore mother cell.