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In angiosperm: Ovules
…a small opening called the micropyle at the top. In angiosperms the presence of two integuments is plesiomorphic (unspecialized), and one integument is apomorphic (derived). A single large megasporocyte arises within the nucellus near the micropyle and undergoes meiotic division, resulting in a single linear tetrad of megaspores. Three of…
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In angiosperm: General characteristics
…received at an opening (the micropyle) atop the ovule.
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In plant development: Preparatory events
…tissues, through an opening (micropyle) of the egg, and enters a cell near the micropyle (synergid), in which the two male gametes are discharged. The unique feature of this phase of angiosperm development is that two fertilizations occur. One male gamete fuses with the egg to give the diploid…
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In plant reproductive system: Seed plants
…is a minute passageway, or micropyle, through the integuments; (4) the ovule matures as a seed; (5) only one megasporocyte is present and undergoes meiosis in the megasporangium to produce four megaspores, only one of which usually is functional; (6) the megaspore is never discharged from its megasporangium and ovule;…
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