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Club-mosses (Lycopodiales) are homosporous, but the genera Selaginella (spikemosses) and Isoetes (quillworts) are heterosporous, with female spores larger than the male. [1] As a result of fertilisation, the female gametophyte produces sporophytes.
The lycophytes, when broadly circumscribed, are a group of vascular plants that include the clubmosses. They are sometimes placed in a division Lycopodiophyta or Lycophyta or in a subdivision Lycopodiophytina. They are one of the oldest lineages of extant (living) vascular plants; the group contains extinct plants that have been dated from the ...
In bryophytes (mosses, liverworts, and hornworts), the gametophyte is the most visible stage of the life cycle. The bryophyte gametophyte is longer lived, nutritionally independent, and the sporophytes are attached to the gametophytes and dependent on them. [5] When a moss spore germinates it grows to produce a filament of cells (called the ...
Lycopodium (from Greek lykos, wolf and podion, diminutive of pous, foot) [2] is a genus of clubmosses, also known as ground pines or creeping cedars, [3] in the family Lycopodiaceae. Two very different circumscriptions of the genus are in use. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), Lycopodium is one of nine genera ...
Mosses are commonly confused with liverworts, hornworts and lichens. [7] Although often described as non-vascular plants, many mosses have advanced vascular systems. [8] [9] Like liverworts and hornworts, the haploid gametophyte generation of mosses is the dominant phase of the life cycle.
A pteridophyte is a vascular plant (with xylem and phloem) that reproduces by means of spores. Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as "cryptogams", meaning that their means of reproduction is hidden. Ferns, horsetails (often treated as ferns), and lycophytes (clubmosses, spikemosses, and ...
Two trends are apparent: bryophytes (liverworts, mosses and hornworts) have developed the gametophyte as the dominant phase of the life cycle, with the sporophyte becoming almost entirely dependent on it; vascular plants have developed the sporophyte as the dominant phase, with the gametophytes being particularly reduced in the seed plants.
The fimbrils characterize wood in arborescent lycopsids, though similar structures occur in modern club and spike mosses, and these fimbrils are a shared structure for all lycopsids. [9] Bordering outside the secondary xylem is a section of cells with thin walls, representing the vascular cambium.