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Antheridia consist of a thin cellular layer that holds many sperm inside. Here, the diagram of a liverwort antheridium is shown. An antheridium is a haploid structure or organ producing and containing male gametes (called antherozoids or sperm). The plural form is antheridia, and a structure containing one or more antheridia is called an ...
The biflagellate sperm must swim from the antheridia, or else be splashed to the archegonia. When this happens, the sperm and egg cell fuse to form a zygote, the cell from which the sporophyte stage of the life cycle will develop. Unlike all other bryophytes, the first cell division of the zygote is longitudinal. Further divisions produce three ...
The sporophyte of many liverworts are non-photosynthetic, but there are also several that are photosynthetic to various degrees. [14] Cells in a typical liverwort plant each contain only a single set of genetic information, so the plant's cells are haploid for the majority of its life cycle. This contrasts sharply with the pattern exhibited by ...
The thallus (tissue) consists of fine branched filaments each with a central axial filament supporting pericentral cells. [7] The number of these pericentral cells (4–24) is used in identification. [8] [9] [10] Polysiphonia elongata [11] shows a central axial cell with 4 periaxial cells with cortical cells growing over the outside on the ...
In hornworts, the meristem starts at the base where the foot ends, and the division of cells pushes the sporophyte body upwards. In mosses, the meristem is located between the capsule and the top of the stalk (seta), and produces cells downward, elongating the stalk and elevating the capsule.
Marchantia is a genus of liverworts in the family Marchantiaceae and the order Marchantiales.The genus was named by French botanist Jean Marchant after his father.. The thallus of Marchantia shows differentiation into two layers: an upper photosynthetic layer with a well-defined upper epidermis with pores and a lower storage layer.
Prothallus: A green, photosynthetic structure that is one cell thick, usually heart or kidney shaped, 3–10 mm long and 2–8 mm broad. The prothallus produces gametes by means of: Antheridia: Small spherical structures that produce flagellate antherozoids. [3]
Plants are usually monoicous, and sexual reproduction is by antheridia and archegonia. Asexual reproduction occurs by spores, by fragmentation of the rosettes, and by formation of apical tubers. Spores are large (45 to 200 μ) and formed in tetrads. [2] The sporophyte of Riccia is the simplest amongst bryophytes. It consist of only a capsule ...