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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 cycle.
Diagram of an anther in cross section. 1: Filament; 2: Theca; 3: Connective (the conducting vessels in red); 4: Pollen sac (also called sporangium) The androecium is one of the fertile cycles of flowers. The parts that make up the androecium are called stamens whose function is the generation of male gametophytes or pollen grains.
Gynoecium (/ ɡ aɪ ˈ n iː s i. ə m, dʒ ɪ ˈ n iː ʃ i. ə m /; from Ancient Greek γυνή (gunḗ) 'woman, female' and οἶκος (oîkos) 'house'; pl.: gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds.
Location of ovules inside a Helleborus foetidus flower. In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the integument, forming its outer layer, the nucellus (or remnant of the megasporangium), and the female gametophyte (formed from a haploid megaspore) in its center.
Heterosporous plants, such as seed plants, spikemosses, quillworts, and ferns of the order Salviniales produce spores of two different sizes: the larger spore (megaspore) in effect functioning as a "female" spore and the smaller (microspore) functioning as a "male".
Or, with bisexual and at least one of male and female flowers on the same plant. [2] Protandrous: (of dichogamous plants) having male parts of flowers developed before female parts, e.g. having flowers that function first as male and then change to female or producing pollen before the stigmas of the same plant are receptive. [6]
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
Pseudautoicous – dwarf male plants growing on living leaves of female plants. Pseudomonoicous – Pseudoperianth – an involucre that resembles a perianth, but is made of thallus tissue, and usually forms after the sporophyte develops. Rhizautoicous – male inflorescence attached to the female stem by rhizoids.