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In botany, a sporophyll is a leaf that bears sporangia. Both microphylls and megaphylls can be sporophylls. In heterosporous plants, sporophylls (whether they are microphylls or megaphylls) bear either megasporangia and thus are called megasporophylls , or microsporangia and are called microsporophylls .
In flowering plants, the gametophytes are very reduced in size, and are represented by the germinated pollen and the embryo sac. The sporophyte produces spores (hence the name) by meiosis , a process also known as "reduction division" that reduces the number of chromosomes in each spore mother cell by half.
A prefix meaning "two", e.g. bisulcate, having two sulci or grooves. biennial A plant which completes its life cycle (i.e. germinates, reproduces, and dies) within two years or growing seasons. Biennial plants usually form a basal rosette of leaves in the first year and then flower and fruit in the second year. bifid
A strobilus (pl.: strobili) is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem.Strobili are often called cones, but some botanists restrict the use of the term cone to the woody seed strobili of conifers.
A sporangium (from Late Latin, from Ancient Greek σπορά (sporá) ' seed ' and ἀγγεῖον (angeîon) ' vessel '; pl.: sporangia) [1] is an enclosure in which spores are formed. [2] It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other groups form sporangia at some point in their life ...
Heterosporous plants that produced microspores in microsporangia and megaspores in separate megasporangia evolved independently in several plant groups during the Devonian period. [ 1 ] Fossils of these plants show that they produced endosporic gametophytes, meaning that their gametophytes were not free-living as in bryophytes but developed ...
The annulus slowly straightens and continues to evert sometimes to the extent that the two ends of the recurved annulus almost meet. As more water evaporates, air bubbles form in the cells causing the contracted annulus to snap forward again, thus dislodging and launching the spores away from the plant. The type and position of the annulus is ...
A female pinecone produces the megaspores of this heterosporic plant. A male pinecone produces the microspores of this heterosporic plant. Heterospory is the production of spores of two different sizes and sexes by the sporophytes of land plants. The smaller of these, the microspore, is male and the larger megaspore is female.