![]() Thyroid imbalance is a systemic problem that starts in the gut. MegaSporeBiotic™ boasts a 5-year shelf-life, does not require refrigeration, and maintains efficacy during antibiotic therapy. This unique all-spore formula effectively RECONDITIONS the gut by promoting microbial diversity and maintaining key health-promoting, commensal gut bacteria. MegaSporeBiotic™ is the first 100% spore-based, broad-spectrum probiotic clinically shown to maintain healthy gut barrier function. The Super-Mom’s Guide to Managing Life with Thyroid & Autoimmune Disease.A Partner’s Guide to Thyroid & Autoimmune Disease.Therefore, upon fertilization the endosperm will be 5N rather than the typical 3N. In Lilium which has a tetrasporic pattern, the central cell of the embryo sac is 4N. The bisporic and tetrasporic patterns undergo varying processes and result in varying embryo sacs as well. Therefore, the resulting embryo sac is a seven-celled structure consisting of one central cell, one egg cell, two synergid cells, and three antipodal cells. At the other end of the cell, a cell wall forms around the nuclei and forms the antipodals. The three nuclei at the end of the cell near the micropylar become the egg apparatus, with an egg cell in the center and two synergids. Depending on the species, these nuclei fuse before or upon fertilization of the central cell. These groups both send a nucleus to the center of the cell these become the polar nuclei. These eight nuclei are arranged into two groups of four. If the monosporic pattern occurred, the single nucleus undergoes mitosis three times, producing an eight-nucleate cell. Some species, such as Tridax trilobata, Ehretia laevis, and Alectra thomsoni, can undergo different patterns of megasporogenesis and therefore different patterns of megagametogenesis. The process of megagametogenesis varies depending on which pattern of megasporogenesis occurred. Plant ovules with megasporocytes before meiosis: Gymnosperm ovule on left, angiosperm ovule (inside ovary) on rightĪfter megasporogenesis, the megaspore develops into the female gametophyte (the embryo sac) in a process called megagametogenesis. The megaspore then undergoes megagametogenesis to give rise to the female. Therefore, each pattern gives rise to a single functional megaspore which contains one, two, or four meiotic nuclei, respectively. The tetrasporic pattern is characterized by cell plates failing to form after either meiosis 1 or 2, and results in one four-nucleate megaspore. The bisporic pattern is characterized by cell plate formation only after meiosis 1, and results in two two-nucleate megaspores, of which one degenerates. This pattern is characterized by cell plate formation after meiosis 1 & 2, which results in four one-nucleate megaspores, of which three degenerate. ![]() The monosporic pattern occurs most frequently (>70% of angiosperms) and is found in many economically and biologically important groups such as Brassicaceae (e.g., Arabidopsis, Capsella, Brassica), Gramineae (e.g., maize, rice, wheat), Malvaceae (e.g., cotton), Leguminoseae (e.g., beans, soybean), and Solanaceae (e.g., pepper, tobacco, tomato, potato, petunia). Angiosperms exhibit three patterns of megasporogenesis: monosporic, bisporic, and tetrasporic, also known as the Polygonum type, the Alisma type, and the Drusa type, respectively. During megasporogenesis, a diploid precursor cell, the megasporocyte or megaspore mother cell, undergoes meiosis to produce initially four haploid cells ( the megaspores). In gymnosperms and flowering plants, the megaspore is produced inside the nucellus of the ovule. ![]()
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